UC-NI 


SB    ES 


LIBRARY 
-CALIFORN 


IA 


IO 


STEAM  MAKING; 


OR 


BOILER  PRACTICE, 


OHAS.  A.  SMITH,  0.  E., 

Professor  of  Civil  and  Mechanical  Engineering  at   Washington   University*  St. 

Louis,  Mo.;  Member  of  the  American  Society  of  Civil  Engineers,  the 

Engineers'  Club  of  St.  Louis,  and  Associate  Member  of  the 

American  Association  of  Railway  Master  Mechanics. 


UNIVERSITY' 


CHICAGO : 
THE  AMERICAN  ENGINEER,  182-184  DEARBORN  STREET. 

1885. 


(o 


Entered  according  to  act  of  Congress,  in  the  year  1884,  l>y 

PROPRIETORS  OF  THE  AMERICAN  ENGINEER, 
in  the  Office  of  the  Librarian  of  Congress,  at  Washington,  D.  C. 


PRESS   OF 

JOHN  W.  WESTON, 
CHICAGO,  ILL. 


PUBLISHERS'  PREFACE. 


It  is  believed  that  some  knowledge  of  the  circumstances  attending  the 
publication  of  this  work,  "STEAM  MAKING,"  as  well  as  its  companion 
volume,  "STEAM  USING,"  will  be  of  interest  to  the  reader. 

The  lamented  author,  Prof.  Chas.  A.  Smith,  had  arranged  with  the 
American  Engineer  for  the  publication  of  the  two  works.  While  the  first, 
"STEAM  MAKING,"  was  going  through  the  columns  of  the  Engineer,  Pro- 
fessor Smith  died,  early  in  1884,  leaving  also  to  the  care  of  the  Engineer 
the  recently  completed  manuscript  of  "STEAM  USING." 

To  all  who  are  familiar  with  the  circumstances  under  which  the  books 
were  written — the  author  suffering  from  a  mortal  illness  and  struggling 
against  death  to  thus  round  out  his  life  work,  only  giving  up  to  die  on  their 
completion — will  appreciate  and  value  the  more  highly  the  broad  and 
active  experience  thus  crystallized. 

To  Mr.  John  W.  Weston,  so  long  connected  with  this  journal,  and 
personally  familiar  with  the  author  and  his  writings,  has  been  delegated 
the  pleasant  duty  of  conducting  these  works  through  the  various  stages 
of  bookmaking,  with  the  result  now  presented.  The  task  has  not  been 
without  its  difficulties,  the  most  serious,  perhaps,  being  the  loss  of  the 
invaluable  assistance  of  their  author  in  the  work  of  revision  of  matter 
and  proof. 

It  has  been  the  aim,  as  far  as  possible,  to  preserve  the  exact  style  of 
the  author,  and  it  is  believed  that  the  facts  and  features  presented  in  both 
books,  the  heirlooms  of  an  admirable  man,  acknowledged  to  be  profound 
and  exact  in  his  particular  lines  of  work,  will  be  held  to  cover  whatever 
defects  of  minor  importance  may  be  encountered. 

THE  AMERICAN  ENGINEER, 

CHICAGO,  January  1,  1885. 


AUTHOR'S  PREFACE. 


In  this  work  the  author  has  aimed  at  the  presentation  of  modern  boil- 
ers and  has  intended  to  give  only  those  sanctioned  by  general  experience 
admitting  nothing,  for  the  sake  of  novelty  or  apparent  advantages. 

In  such  a  work  there  can  be  little  originality  and  the  author  is,  of 
course,  indebted  to  many  sources  for  his  information.  The  examples 
chosen  are  taken  from  American  practice  where  possible.  The  four  ma- 
rine boilers  and  the  boiler  at  Mulhouse  are  taken  from  "Engineering"  as 
also  the  tables  of  experiments  with  rivetting  and  with  the  full  sized  boil- 
ers. To  Mr.  L.  E.  Fletcher  the  author  is  greatly  indebted  for  permission 
to  use  his  valuable  paper  on  the  Lancashire  boiler  in  Chapter  IV.,  and  to 
H.  K.  Ivers,  Assistant  Engineer,  United  States  Navy,  for  valuable  assist- 
ance in  preparing  illustrations.  Two  good  works  on  boilers  have  recently 
appeared  in  this  country:  The  able  work  of  Chief  Engineer  Shock, 
United  States  Navy,  which  treats  mainly  of  the  marine  boiler,  and  that  of 
Mr.  Wm.  Barr,  of  Indianapolis.  The  former  is  placed  by  its  price  beyond 
the  reach  of  many,  and  the  latter  gives  more  attention  to  Western  prac- 
tice. In  this  book  the  attempt  has  been  made  to  give  a  more  comprehen- 
sive view  of  the  ground  than  either  of  these  authors,  while  necessarily 
many  of  the  facts  given  are  to  be  found  in  those  works.  On  the  practical 
construction  of  boilers  nothing  better  has  appeared  than  the  work  of  Wil- 
son, which  is  not,  however,  illustrated  by  examples  in  detail.  The  author 
would  have  wished  this  work  to  be  illustrated  much  more  fully,  but  for 
the  desire  to  keep  down  the  cost  to  a  reasonable  limit. 

The  table  of  experiments  with  boilers  is  compiled  from  all  sorts  of 
sources  and  is  believed  to  be  sufficiently  extensive  to  furnish  a  precedent 
for  almost  any  kind  of  boiler  in  any  locality;  however,  nothing  better 
than  the  deductions  of  Kankine  and  Clark  have  been  made  from  them. 

It  was  originally  intended  to  include  in  this  work  the  use  of  steam  and 
to  give  an  extended  table  of  engine  trials  and  a  few  examples  of  engines 
but  the  work  has  had  to  wait,  and  may  follow  this  at  some  future  time. 

CHAS.  A.  SMITH. 


SKETCH  OF  THE  LIFE  AND  CHARACTER 
OF  THE  AUTHOR. 


Charles  A,  Smith  was  born  in  St.  Louis,  October  1,  1846.  His  parents 
were  both  Massachusetts  people  who  had  been  still  further  west.  From 
both  father  and  mother  he  inherited  the  instincts  of  a  sailor,  and  the 
blood  of  several  generations  of  ship-masters  coursed  through  his  veins. 
Though  he  never  became  a  sailor,  he  always  showed  a  sailor's  fondness  for 
"fixing  things,"  for  using  his  hands,  for  actual  construction. 

While  he  was  still  an  infant,  his  mother  died  of  cholera  in  St.  Louis, 
and  he  was  placed  in  the  care  of  his  father's  sister,  in  Newburyport,  Mass. 
This  kind  aunt  was  his  mother,  and  her  house  was  his  home  till  he  had  a 
home  of  his  own.  His  mode  of  life  was  simple  and  plain,  but  young 
Smith  made  warm  friends  and  his  boyhood  was  happy. 

I  first  met  him  in  1860,  when  I  became  principal  of  the  Boys'  High 
School,  of  Newburyport.  He  was  then  fourteen  years  old  and  a  member 
of  the  second  class.  He  was  a  pleasant  little  fellow  with  a  frank,  earnest 
look,  and  a  forehead  which  suggested  brains.  When  the  school  gave 
expression  to  its  loyalty  to  the  Union  by  the  erection  of  a  liberty  pole  and 
publicly  celebrated  a  flag-raising,  young  Smith  was  selected  by  his  school- 
mates to  mount  the  platform  and  haul  home  the  stars  and  stripes. 

The  school  had  a  very  good  theodolite,  and  when  we  came  to  Loomis' 
Surveying,  a  great  enthusiasm  for  field  work  was  developed,  and  young 
Smith  was  never  so  happy  as  when  on  a  surveying  party.  He  took  the 
English  course  and  graduated  in  1862.  The  next  spring  he  went  into  the 
office  of  J.  B.  Henck,  civil  engineer,  in  Boston.  At  that  time  he  probably 
had  no  idea  of  going  to  an  engineering  school.  In  1864  he  was  leveller  on 
the  Boston,  Hartford  &  Erie  Kailway.  In  1865  he  became  chief  assistant 
in  the  City  Engineer's  office,  Springfield,  Mass.  By  this  time  he  saw 
clearly  that  an  engineer  requires  a  training  far  beyond  a  high  school 
education,  and  he  resolved  to  enter  the  Massachusetts  Institute  of  Tech- 
nology, then  first  opened.  He  had  been  reading  ahead  somewhat,  with 
occasional  help  from  me,  so  that  he  entered  what  was  organized  as  a 
sophomore  class.  He  lived  again  in  Newburyport  and  went  eighty  miles 
daily  on  his  way  to  and  from  the  Institute.  President  Kogers  was  his 
teacher  in  physics,  Professor  Kunkle  in  mathematics  and  applied  mechan- 
ics, and  Professor  Henck  in  civil  engineering. 

He  graduated  in  the  pioneer  class  in  1868.  I  never  quite  understood 
how  he  managed  to  meet  the  cost  of  his  course  at  the  Institute.  To  be 
sure  he  had  carefully  saved  the  earnings  of  three  years,  and  he  secured 


VIII.  STEAM  MAKING;  OR,  BOILER  PRACTICE. 

for  his  vacations  most  excellent  employment  under  the  celebrated  hy- 
draulic engineer,  J.  B.  Francis,  at  Lowell,  Mass.  He  there  assisted  in 
determining  the  flow  of  water  in  pipes,  over  wiers,  the  efficiency  of  tur- 
bines, etc.  I  left  Massachusetts  for  St.  Louis  in  1865,  so  I  did  not  follow 
closely  his  career  as  a  student. 

After  a  year  as  engineer  on  the  Union  Pacific  Kailway  in  Utah,  he 
returned,  on  the  completion  of  the  road,  to  Boston  and  went  into  partner- 
ship with  Professor  J.  B.  Henck.  as  civil  engineers.  While  there  associated 
with  Professor  Henck,  he  took  charge  of  a  part  of  the  Blue  Eidge  Rail- 
way  of  North  Carolina,  as  division  engineer. 

At  that  time,  in  1870,  the  steady  development  of  the  Polytechnic 
School  of  Washington  University  made  it  necessary  to  appoint  an  instruc- 
tor of  civil  engineering.  I  took  pleasure  in  recommending  young  Smith 
for  the  position,  and  he  was  appointed.  For  the  first  year  he  made  his 
home  in  my  family,  and  as  a  preparation  for  the  work  of  the  class  room  he 
read  with  me  Kankine's  Civil  Engineering  entire. 

After  a  brief  experience  as  instructor,  Mr.  Smith  was  appointed  pro- 
fessor to  the  chair  of  civil  and  mechanical  engineering,  which  was  subse- 
quently named  in  honor  of  William  Palm.  This  chair  Professor  Smith 
held  till  June,  1883,  when  compelled  by  his  last  illness  to  resign. 

Though  devoted  at  all  times  to  the  work  of  his  professorship,  Profes- 
sor Smith  found  time  to  mingle  in  matters  of  practical  engineering.  For 
five  years  he  was  consulting  engineer  of  the  Iron  Mountain  Railway, 
among  other  things  designing  the  DeSoto  shops,  and  building  a  new  pier 
in  the  Black  river.  In  a  similar  way  he  was  associated  with  Messrs. 
Shickle,  Harrison  &  Co.,  designing  the  arched  ribs  of  the  roof  over  the 
Chamber  of  Commerce,  and  the  iron  trestles  of  the  Bessemer  Iron  Works. 
Professor  Smith  was  engaged  as  consulting  engineer  for  the  construction 
of  the  water  works  of  Hannibal,  of  St.  Charles,  in  Missouri,  and  of  Ames- 
bury,  Massachusetts.  His  last  professional  duties  were  in  connection  with 
the  last  named.  The  pumping  works  at  Richmond,  Va.,  were  designed  by 
him,  his  plans  being  entered  in  competition  and  receiving  the  first  prize. 
In  1879  he  spent  his  summer  vacation  as  resident  engineer  of  the  Balti- 
more Bridge  Company,  building  piers  in  the  Mississippi  river  just  below 
Minneapolis. 

Without  attempting  to  give  a  full  list  of  the  professional  enterprizes 
of  Professor  Smith,  I  have  said  enough  to  show  how  tireless  a  worker  he 
was,  and  how  closely  he  studied  the  practical  details  of  engineering.  But 
it  was  in  connection  with  the  St.  Louis  Engineers'  Club  that  his  devo- 
tion and  enthusiasm  were  most  fully  shown.  He  was  an  active  mem- 
ber for  twelve  years,  and  the  secretary  for  nine  or  ten  years.  The  club 
has  not  always  been  as  flourishing  as  it  is  now.  It  has  had  its  seasons  of 
depression  when  only  the  zeal  and  the  courage  of  Secretary  Smith  seemed 
to  hold  it  together.  Nothing  but  the  direst  necessity  compelled  him  to 
yield  at  last. 

The  fatal  malady,  which  in  the  shape  of  a  cancerous  tumor,  brought 
his  life  to  an  untimely  close  on  the  2nd  of  February,  1884,  was  born,  as  he 


L  JFE  A  ND  GHA  RA  C  TE  R  OF  THE  A  ITT H OR.  I X . 

i 

thought,  of  hard  work,  of  exposure,  and  of  physical  neglect.    He  could 
scarcely  stop  to  eat  or  sleep;  it  was  work  first  and  comfort  last. 

Nothing  in  Professor  Smith's  life  was  more  heroic  than  the  way  he 
battled  for  two  years  against  an  impending  fate.  When  too  weak  to  stand 
before^  his  \class,  he  taught  reclining  upon  a  lounge.  One  of  his  last 
pupils  speaks  in  a  notice  of  his  beloved  professor  of  "the  days  of  suffer- 
ing spent  in  his  study  in  the  University,  when  we  gathered  round  him 
as  he  lay  on  the  lounge,  unable  to  stand,  and  listened  to  his  exposition 
of  'Economic  Location,'  taking  as  a  basis  the  work  of  his  friend,  Arthur 
Wellington." 

In  January,  1883,  he  was  forced  to  give  up  his  class  work  altogether, 
and  to  keep  his  room.  Still  he  was  not  idle.  Lying  on  the  bed,  or  reclin- 
ing in  an  easy  chair,  he  was  hard  at  work  upon  his  two  books  on  "Steam 
Making"  and  "Steam  Using,"  which  are  just  now  being  issued  by  the' 
American  Engineer,  in  Chicago.  The  first  was  finished  by  the  end  of 
1882,  and  arrangements  were  made  for  its  publication,  but  the  prospect 
for  the  second  book  was  gloomy  enough.  Nevertheless,  he  worked 
at  it  with  a  terrible  earnestness  which  no  unfavorable  symptom  could 
diminish.  Nay,  though  clinging  to  the  faintest  glimmer  of  hope  of 
returning  health,  he  toiled  at  his  book  with  the  resolute  air  of  one  who 
was  fully  conscious  that  his  days  were  numbered,  and  that  the  book  must 
speedily  be  finished.  In  spite  of  pain  and  the  dark  shadow  of  the  inevit- 
able, his  mind  seemed  clear  and  his  hand  steady.  In  the  spring  of  '83 
he  moved  back  to  Newburyport,  Mass.,  to  be  near  his  physician  and  his 
family  friends.  There  in  a  quaint  old  house,  in  a  quiet  neighborhood  of 
that  quiet  town,  he  finished  his  book,  laying  down  his  pen  and  the  burden 
of  life  at  the  same  time.  The  readers  of  "Steam  Using"  may  be  glad  to 
know  that  the  author's  very  life's  blood  went  into  that  book;  that  it  was 
the  last,  the  most  perfect  fruit  of  a  very  active  and  noble  life.  . 

Professor  Smith  is  a  good  example  of  a  poor  boy  who  made  his  own 
way;  who  fought  his  own  battles;  who  earned  and  honored  every  position 
he  took.  He  was  always  a  student.  Some  of  you  will  remember  with 
what  enthusiasm  he  studied  quarternions  and  thermodynamics;  with 
what  zeal  and  success  he  read  all  that  he  could  get  on  graphical  statics, 
and  how  many  important  additions  he  suggested.  The  records  of  the 
St.  Louis  Club  probably  will  show  that  Professor  Smith  has  presented 
more  papers  than  any  other  member,  past  or  present. 

As  an  engineer,  Professor  Smith,  was  bold  and  trustworthy.  His  confi- 
dence was  based  upon  sound  theory  and  careful  practice.  He  was  skillful 
in  preparing  estimates  and  was  always  well  informed  both  as  regards  the 
latest  improvements  in  engineering,  and  the  best  methods  of  working  the 
materials  of  construction. 

These  accomplishments  added  greatly  to  his  value  as  an  instructor  of 
young  engineers.  His  students  were  brought  very  close  to  engineering 
work.  Though  well  read  in  theory,  he  loved  to  dwell  on  the  details  of 
practice.  He  never  lost  an  opportunity  to  learn  a  new  process,  or  to  study 
a  new  machine.  He  used  to  tell  how,  while  resident  engineer  on  a  road  in 


STEAM  MAKING;  OR,  BOILER  PRACTICE 


New  England,  he  tried  his  hand  on  the  engine  of  the  construction  train 
till  he  was  able  to  "stoke"  and  to  "drive." 

Professor  Smith  left  a  wife  and  three  children.  During  her  husband's 
long  and  discouraging  sickness,  Mrs.  Smith  was  better  than  a  faithful 
nurse:  she  brought  aid  to  his  self-imposed  labor,  and  hope  and  cheer  to 
his  fainting  spirit.  So  well  did  she  understand  the  nature  of  his  work 
and  his  needs,  and  so  helpful  was  the  assistance  she  brought,  that  it  is  not 
too  much  to  say  that  without  her  positive  cooperation  and  encouragement 
the  two  books  which  he  leaves  behind  would  never  have  been  finished. 

I  will  not  speak  of  personal  losses.  I  prefer  to  feel  that  we  all  had 
much  to  be  thankful  for  in  Professor  Smith,  and  the  nearest  had  the  most. 
Though  dying  in  his  thirty- eighth  year,  Professor  Smith's  memory  may 
well  be  preserved.  The  world  is  certainly  the  better  for  his  having 
lived  in  it. 

C.  M.  WOODWAKD, 

Dean  Polytechnic  School, 
Washington  University,  St.  Louis,  Mo. 

ST.  Louis,  December,  7,  1884. 


OOItTTIEItTTS. 


CHAPTER  I. 

PAGE. 
ON  THE  NATURE  OF  HEAT  AND  THE  PROPERTIES  OF  STEAM: — 

Heat — Thermodynamics — Ratios  of  Volume  to  Pressure :  Regnault's  Ratios — 
The  Carnot  Engine— Making  Steam— Measurement  of  Heat  Expended 
—Table:  The  Properties  of  Saturated  Steam— Examples  in  Calculation 
of  Heat  Expended,  Etc.— Table:  Factors  of  Evaporation— Its  Use- 
Table  :  Expansion  and  Density  of  Pure  Water— Entrained  Water  and 
its  Measurement ...  1—14 


CHAPTER   II. 

ON  COMBUSTION: — 

Principles  of  Combustion— Evaporative  Power  of  Fuels— Losses  by  Imper- 
fect Combustion— Effects  of  Air  on  Combustion,  Quantity  Required, 
and  Quality  of  Certain  Coals— Loss  of  Heat  by  Radiation  and  Conduc- 
tion—Height of  Stack— Tables  of  Boiler  Trials 15—46 


CHAPTER  III. 

EXTERNALLY  FIRED  STATIONARY  BOILERS:— 

Boilers,  their  Shapes  and  Classes— Specification  for  Boilers  for  Meier  Iron 
Company— Setting— Boilers  for  Nova  Scotia  Iron  Company— "French' 
Boiler  Tried  at  Mulhouse— Water  Tube  Boilers— Boilers  on  Mississippi 
River  Boats:  the  "Montana"— Specification  of  Boilers  for  La  Clede 
Rolling  Mills— Boilers  for  the  St.  Louis  Lead  and  Oil  Company— Speci- 
fication for  60-inch  Horizontal  Tubular  Steam  Boiler— Upright  Boilers.  47—  73 


CHAPTER  IV. 

INTERNALLY  FIRED   STATIONARY  BOILERS: — 

The  Lancashire  Boiler— Cornish  Boiler  at  Dusseldorf— Specification  for  Gal- 
loway Boiler  for  Crystal  Plate  Glass  Company 74—100 


XII.  CONTENTS. 


CHAPTER    V. 

PAGE. 
INTERNALLY  FIRED  PORTABLE,  LOCOMOTIVE  AND  MARINE  BOILERS:— 

Varieties  of  Boilers— Locomotive  Boiler  for  Engine  No.  150,  Wabash,  St. 
Louis  &  Pacific  Railway — Boiler  for  "Consolidation  Locomotive,"  Mis- 
souri Pacific  Railroad — Marine  Boilers — Boilers  of  H.  M.  S.  "Rover" — 
Steel  Boiler,  Wallsend  Slipway  Co.,  Newcastle-Upon-Tyne— Boilers  of 
S.  S.  "Assyrian  Monarch" — Boilers  for  S.  S.  "Mexican" — Boilers  of  the 
Cunard  Steamship  "Servia"— Steam  Fire  Engine  Boilers— The  Herreshoff 
Boiler...  ...101—119 


CHAPTEK   VI. 

THE  DESIGN,  CONSTRUCTION  AND  STRENGTH  OF  BOILERS;— 

The  Special  Features— United  States  Laws,  Regulation  and  Inspection,  Steam 
Pres:ure,  Quality  of  Plates,  Appurtenances — Table  of  Pressures  Allow- 
able— Table  of  Pressures,  Etc.,  Allowable  on  Freight  and  Towing  Ves- 
sels— Rules  and  Regulations  Relating  to  Pressures,  Boilers,  and  the 
Inspection  of  Boiler  Plates— Laws  Relating  to  Instruments— Discipline 
—Instruments,  Machines  and  Equipments  Approved  for  Use  with 
Steamship  Boilers— Extracts  from  English  Board  of  Trade  Rules— 
Rivetting— Experiments  by  David  Greig  and  Max  Eyth,  and  Conclu- 
sions— Conclusions  of  United  States  Board  of  Engineers  on  Bolts,  in 
Plates— Eye  Bars  and  Tie  Stays— Strength  of  Flues 120—148 


CHAPTER    VII. 

DESIGN  AND  CONSTRUCTION  CONTINUED — PROPORTIONS  OF  HEATING 
SURFACE,  ETC. — ECONOMIC  EVAPORATION — EXPLOSIONS: — 

Experiments  on  the  'Collapsing  of  flues — Tests  Made  by  the  Manchester 
Steam  Users'  Association  upon  a  Lancashire  Boiler — Experiments  by 
Messrs.  John  Elder  &  Company— Durability :  Corrosion— Experiments 
on  Steel  by  Wm.  Boyd— Mr.  W.  Parker  on  Marine  Steel  Boilers— Mr. 
Robert  Wilson's  Conclusions  on  Water-Tube  Boilers— Circulation  of 
Water— On  Heating  Surface -Table  of  Desirable  Efficiencies  for  Various 
Pressures  and  Times  Between  Coaling  for  Ordinary  Marine  Boilers, 
Ordinary  Draft— Cost  of  Fuel,  Etc.— Questions  of  Cost,  Economy,  Etc. 
—The  Style  of  Boiler  for  Various  Conditions,  Etc.— Boiler  Explosions- 
Explosion  Experiments — Conclusions 1 49 — 1(57 


CHAPTER   VIII. 

MISCELLANEOUS  BOILERS — CHOICE  OF  BOILER  FITTINGS  AND  AP- 
PURTENANCES:— 

Fuels :  Qualities,  Quantities,  Etc.— Quality  of  Water— Ogle's  Boiler— Perkin's, 
Benson's,  Belleville,  Latta,  and  Herreshoff  Boilers— Heine,  Root  and 
Firmenich  Boilers— "Anthracite"  Boiler— Kelly's,  Shepherd's  and  the 
Harrison  Boilers— Boiler  Appurtenances— Feed -water  Heaters— Feed 
Pumps— Injectors— Steam  Blast  — Blow-off  Valves  —  Gauges  —  Safety 
Valves,  Etc.,  Etc 108-195 


OR 

BOILER     PRACTICE. 


CHAPTER      I. 

ON  THE  NATURE  OF  HEAT  AND  THE  PROPERTIES  OF  STEAM. 

By  the  term  heat  we  understand  that  property  of  bodies  by  which  they 
grow  hot,  and  give  the  sensation  with  which  we  are  all  familiar. 

Heat  is  produced  in  three  ways: 

By  chemical  action,  A. 

By  mechanical  action,  B. 

By  electrical  action,  C. 

A. — When  certain  chemical  elements  or  compounds  are  combined  under 
certain  circumstances,  the  result  is  a  union  accompanied  by  an  increase  of 
temperature  and  the  development  of  heat;  as  for  example,  carbon  or  hydro- 
gen combining  with  oxygen;  sulphuric  acid,  or  quick  lime  with  water. 

B. — By  the  mechanical  work  of  friction  or  percussion:  Examples  of 
this  are  continually  before  us. 

C. — By  the  passage  of  an  electric  current  in  a  conductor, — as  in  wires  of 
too  great  resistance;  or  the  electric  arc. 

The  property  of  heat  is  thought  by  some  to  consist  of  a  kind  of  motion 
or  vibration  of  the  molecules  of  which  bodies  are  supposed  to  consist; — tor 
solid  and  liquid  bodies  in  vibration,  and  for  gaseous  bodies  in  the  real  mo- 
tion of  the  molecules.  With  the  arguments,  pro.  or  con.,  concerning  this  hy- 
pothesis we  have  little  to  do  further  than  to  state  that,  its  truth  appears 
very  probable,  and  in  such  event  the  production  of  heat  by  chemical  com- 
bination or  the  passage  of  an  electric  current  is  simply  a  kind  of  mechani- 
cal action;  in  the  one  case,  the  vibration  resulting  from  the  shock  of  mole- 
cules attracting  each  other;  in  the  other,  from  the  setting  up  of  a  wave 
movement,  or  kind  of  wave,  in  the  path  of  the  electric  disturbance  whatever 
that  may  be. 

That  heat  was  produced  by  mechanical  means  has  been  long  known. 
While  the  identity  of  heat  and  mechanical  force  was  suspected  by  Count 
Kumford  nearly  a  hundred  years  ago,  it  was  reserved  for  Joule  to  prove 
(by  long  continued  experiment),  that  the  same  quantity  of  work  always 
gave  the  same  quantity  of  heat,  and  to  Kankine  and  Clausius  to  show, 
theoretically  that,  the  same  quantity  of  heat  always  gives  the  same  amount 
of  work,  which  has  since  been  proved  beyond  all  doubt  by  experimental 
investigations. 

By  the  labors  of  the  two  great  men,  Kankine   and    Clausius,  the 


STEAM  MAKING;   OR,  BOILER  PRACTICE. 


science  of  thermodynamics  was  created, — the  application  of  mathematics 
it  the  laws  of  heat.  Of  this  interesting  and  beautiful  science  we  shall, 
however,  only  state  the  two  fundamental  principles: 

First  Principle — "Heat  and  mechanical  energy  are  mutually  convertible, 
"and  heat  requires  for  its  production  and  produces  by  its  disappearance 
"mechanical  energy  in  the  proportion  of  772  foot-pounds  for  each  British 
"unit  of  heat." 

The  British  unit  of  heat,  just  mentioned,  is:  "The  quantity  of  heat 
"which  corresponds  to  an  interval  of  one  degree  of  Farenheit's  scale  in  the 
"temperature  of  one  pound  of  pure  liquid  water  at  and  near  its  temperature 
"of  greatest  density  (39.1°F)." 

The  second  principle,  as  given  by  Clausius,  is  as  follows: 

Second  Principle. — "Heat,  of  itself,  never  passes  from  a  cold  body  to  a 
hotter  one. " 

Rankine  states  the  second  principle  in  a  way  that  has  been  severely 
criticised  by  Maxwell,  but  which  appears  to  mean  that,  a  unit  of  heat  in  a 
cold  body  can  do  as  much  work  as  in  a  hot  body,  with  the  implied  reserva- 
tion that  there  must  be  yet  a  colder  body  into  which  it  may  pass. 

Heat  is  converted  into  mechanical  work  through  the  agency  of  some 
body  that  is  expanded  by  heat,  such  as  air  or  water.  The  heat  is  transferred 
into  these  mediums,  usually  enclosed  within  limits  of  changeable  volume, 
the  expanding  medium  enlarging  the  volume  against  a  resistance  thereby 
does  mechanical  work. 

It  has  been  taken  for  granted  that  the  word  temperature  was  under- 
stood to  have  its  ordinary  meaning,  and  that  neither  the  ordinary  thermo- 
metric  scales  of  temperature,  nor  the  ordinary  instruments  used  for  meas- 
uring temperature  required  description;  but  when  great  accuracy  was 
required,  the  use  of  the  air  thermometer  drew  attention  to  a  very  con- 
venient scale.  Dry  air  and  some  of  the  other  gases  increase  in  volume  or 
pressure  from  the  temperature  of  melting  ice  to  that  of  boiling  water  under 
the  atmospheric  pressure  as  follows: 

From  the  volume  or  pressure  1  to: 

Constant  Volume.  Constant  Pressure. 


Air  

1  3665 

1  3670 

Hydrogen  

1  3667 

1.3661 

Nitrogen         

1  3668 

Carbonic  Acid  

1  3688 

1  3669 

Carbonic  Oxide   . 

1  3667 

1  3719 

Nitrous  Oxide  

1  3676 

1  3719 

Cyanogen  

1.3829 

1.3877 

Sulphurous  Acid  

1.3843 

1.3903 

NOTE.— The  above  ratios  are  from  Regnault. 

With  the  air  thermometer  the  change  in  volume  of  a  portion  of  dry  air 
was  used  to  measure  the  change  in  temperature,  and  the  natural  result  was 
that  the  temperature  at  which  the  dry  gas  would  have  no  volume,  if  the 
law  should  hold  so  far,  was  taken  as  the  zero  or  starting  point  of  such  a 
scale.  This  zero  is  —461°  F.  or  —273°  C.,  and  is  called  "absolute  zero,"  and 


NA  TURE  OF  HE  A  T  AND  PROPERTIES  OF  STEAM.  3 

temperatures  measured  on  this  scale  are  called  "absolute  temperatures." 
We  shall  give  later  another  and  better  reason  for  this  scale  and  its  name, 
for  we  know  now  that  all  the  gases  above  given  can  be  reduced  to  liquids 
and  solids  and  therefore  are  not  perfect  gases. 

A  perfect  or  "reversible"  engine  was  devised  by  Sadi  Carnot;  and 
although  such  an  engine  cannot  be  constructed,  and  if  constructed,  could 
not  be  worked;  still  it  is  extremely  useful  in  assisting  our  conceptions  and 
in  giving  us  a  limit  beyond  which  we  cannot  hope  to  proceed  with  im- 
provements. 

The  operation  of  the  Carnot  engine  is  as  follows:  From  a  hot  body,  at 
temperature  Tlt  a  working  body  receives  heat  at  the  same  temperature  Tlt 
expanding  and  doing  work  from  the  heat  in  the  hot  body  directly.  After 
a  time  the  hot  body  is  withdrawn,  leaving  the  working  body  at  the  same 
temperature  Tlt  and  it  then  expands  by  virtue  of  the  heat  which  it  contains 
until  its  temperature  has  fallen  to  T2.  In  expanding,  more  work  has  been 
effected,  which,  of  course,  goes  to  the  credit  of  the  engine  as  work  done. 
At  the  temperature  Tv  the  working  body  is  brought  into  contact  with  a 
body  called  the  "cold  body,"  at  the  same  temperature  T2;  work  is  then  done 
on  the  working  body  from  the  outside  in  compressing  it  to  such  a  point, 
heat  meanwhile  passing  from  the  working  body  to  the  cold  body  at  the 
same  temperature.  So  that  by  continuing  the  process  of  compression  after 
the  removal  of  the  cold  body,  the  working  body  will  have  just  reached  its 
first  state  of  volume,  pressure  and  temperature;  the  work  expended  in 
the  two  compression  processes  is,  of  course,  to  the  debit  of  the  engine,  but 
there  is  on  the  whole  a  balance  of  work  done  by  the  engine. 

It  can  be  shown  in  this  case,  whatever  be  the  working  substance 
used:  First. — That  this  engine  utilizes  more  heat  than  can  be  utilized  by 
any  other  kind  of  engine  working  between  the  same  temperatures  2\  and 
To.  Second. — That  the  work  done,  or  heat  utilized,  is  to  the  heat  expended 
from  the  hot  body,  as  the  difference  between  the  temperatures  between 
which  the  engine  works,  T^  —  T2  is  to  the  absolute  temperature  of  the  hot 
body  2\.  Hence  the  fraction 

T,-  Tz 

T, 

where  T  is  an  absolute  temperature,  is  known  as  the  efficiency  of  the 
engine,  and  is  the  maximum  efficiency  which  can  be  reached  by  theory. 

The  proof  of  the  above  statements  is  given  in  any  work  on  thermody- 
namics, so  that  we  shall  not  enter  upon  it  here,  believing  it  out  of  place 
in  a  work  of  a  practical  character. 

From  the  properties  of  the  Carnot  engine,  a  scale  of  temperature, 
based  upon  the  work  done  by  a  body  when  2\  —  T2  =  1°,  is  established; 
and  it  has  been  shown  that  the  scale  thus  established  coincides  in  origin 
and  amount  with  that  of  the  perfect  gas  thermometer,  which  places  it  upon 
a  more  substantial  basis. 

When  heat  is  put  into  any  body  it  may  either  increase  the  agitation  of 
its  molecules,  thereby  heating  it  or  raising  its  temperature;  or  it  may  ex- 
pand it  against  an  external  resistance  doing  external  work;  or  it  may 


4  STEAM  MAKING;   OR,  BOILER  PRACTICE. 

change  its  condition,  overcoming  molecular  attractions,  doing  what  is 
called  internal  work;  or  it  may  do  two  or  three  of  these  three  things  at  the 
same  time. 

When  a  fire  is  lighted  under  a  boiler  containing  cold  water,  the  heat 
generated  by  the  chemical  action  of  combustion  passes  from  the  fire  and 
the  gaseous  products  of  combustion  to  the  iron  of  the  boiler,  through  the 
iron  of  the  boiler  to  the  surface  in  contact  with  the  water  and  thence  into 
the  water.  The  volume  of  the  water  slightly  increases  with  the  tem- 
perature, raising  the  level  partly  by  its  own  increase  in  volume  and  partly 
by  the  increase  in  volume  of  the  air  contained  in  the  water.  The  heat 
increases  the  molecular  agitation  of  the  water,  till,  usually  at  the  tempera- 
ture of  212°  F.,  the  boiler  begins  to  make  steam.  If,  as  in  many  of  the 
boiler  trials,  the  man-head  or  safety  valve  is  open;  or,  as  in  a  common  tea 
kettle,  there  is  no  other  pressure  than  that  of  the  air  upon  the  water,  at 
this  temperature  the  water  remains;  and  all  the  heat  going  into  it  is 
expended  in  overcoming  the  molecular  attraction  of  one  atom  of  water 
for  another,  and  in  forcing  the  molecules  apart.  In  thus  overcoming  the 
molecular  attraction  it  is  doing  internal  work,  and  at  the  same  time  in  lift- 
ing the  atmosphere  by  the  steam  formed,  it  is  performing  external  work. 

"When  the  quantities  of  heat  which  a  pound  of  water  requires  to  raise  it 
from  the  temperature  of  melting  ice  into  steam  at  any  given  pressure  are 
measured,  that  which  it  takes  to  raise  the  temperature  is  not  exactly  the  dif- 
ference in  the  temperatures  which  would  be  required  if  the  specific  heatof 
water  were  constant,  but  a  unit  of  heat  raises  the  temperature  of  a  pound 
of  water  a  little  less  than  one  degree  at  the  higher  temperatures.  When  a 
boiler  is  making  steam  at  a  given  pressure  other  than  that  of  the  atmos- 
phere, there  is  a  temperature  at  which  steam  forms  from  the  water  and 
above  which  the  water  cannot  be  raised.  This  is  known  as  the  tempera- 
ture of  evaporation  for  the  pressure.  It  is  to  be  noted  that  the  pressure  of 
the  atmosphere  may  be  partly  removed  and  low  pressure  steam  formed  at 
less  than  atmospheric  pressure. 

The  quantity  of  heat  required  to  evaporate  a  unit  of  weight  of  water 
at  different  pressures,  and  to  raise  the  temperature  up  to  that  of  evapora- 
tion, was  carefully  determined  by  Regnault  in  an  extensive  series  of 
experiments  made  at  the  expense  of  the  French  Government.  The  volume 
of  one  pound  weight  of  steam,  and,  of  course,  its  reciprocal,  the  density  or 
weight  of  a  cubic  foot  of  steam,  was  determined  by- experiments  made  by 
Fairbairn  and  Tate. 

From  the  heat  of  evaporation,  the  volume  of  steam,  the  pressure  under 
which  it  was  evaporated,  and  the  volume  of  the  water  from  which  it  was 
formed  are  computed: 

First. — The  external  work  in  foot-pounds,  or  the  product  of  the  pres- 
sure in  pounds  per  square  foot  by  the  difference  in  cubic  feet  of  the  volume 
of  one  pound  of  steam  and  one  pound  of  water. 

Second. — The  external  work  in  heat  units  obtained  by  dividing  the  ex- 
ternal work  in  foot-pounds  by  772. 


XA  TURE  OF  HE  A  T  AND  PROPERTIES  OF9STEA  M.  5 

Third. — The  internal  work  of  evaporation  obtained  by  deducting  from 
the  heat  of  evaporation  the  external  work  found  above. 

Fourth. — The  sum  of  the  internal  work  of  evaporation  and  the  heat 
expended  in  raising  the  temperature, — sometimes  called  the  total  internal 
heat. 

Fifth.—  The  sum  of  the  heat  expended  in  raising  the  temperature  of  the 
water,  and  the  heat  of  evaporation;  or,  the  sum  of  the  total  internal  heat 
and  the  external  work  in  heat  units;  or,  the  sum  of  the  heat  expended  in 
raising  the  temperature,  in  internal  work  of  evaporation  and  in  external 
work,  is  called  the  total  heat.  These  quantities  may  all  be  stated  in  foot- 
pounds, and  some  writers  prefer  to  use  them  in  this  way.  But,  although  the 
measurement  of  mechanical  work  is  usually  made  in  foot-pounds,  all  meas- 
urements of  heat  and  steam  which  require  measurements  of  temperature 
are  best  made  with  a  thermometer,  and  by  heat  units;  we  shall,  therefore, 
retain  the  heat  units.  There  is  also  this  advantage,  that  in  computation 
there  will  be  smaller  numbers  and  less  figures  involved. 

The  measurement  of  the  heat  expended  in  raising  the  temperature  o* 
water,  in  the  total  internal  heat  and  the  total  heat,  are  all  based  on  a  start- 
ing point  of  one  pound  of  water  at  the  temperature  of  melting  ice.  As,  how- 
ever, such  quantities  are  usually  used  by  differences,  many  writers  give 
these  data  from  0°  F.  Of  course  this  does  not  require  any  real  existence 
to  the  imaginary  pound  of  water,  as  water  assumed  in  this  way.  It  gives 
a  little  less  numerical  work  with  feed  water  at  low  temperature,  but  is  of 
no  help  when  the  specific  heat  has  varied  so  as  to  alter  the  heat  expended 
in  raising  the  temperature  of  the  water  from  the  difference  between  the 
temperature  and  32°.  We  adhere  to  the  basis  of  melting  ice. 

Most  of  the  theoretical  writers  use  as  a  base  for  the  tables  the  temper- 
ature of  evaporation,  although  others  use  the  pressure, — a  much  more 
practical  starting  point  for  engineers.  But  these  writers  have  not  given 
the  internal  and  external  heats,  have  used  in  some  cases  the  0°  F.  start- 
ing point  referred  to  above,  and  have  given  extended  decimals.  In  our  own 
table  we  have  only  given  the  nearest  heat  unit,  and  have  given  a  table,  not 
for  every  pound  of  pressure,  it  is  true,  but  one  in  which  it  is  very  easy  to 
interpolate  the  nearest  unit.  We  believe  this  table  to  be  convenient  for 
use  and  sufficiently  extended  and  accurate. 

The  heat  of  evaporation  is  called  latent  heat  of  evaporation,  but  as  the 
term  latent  has  now  no  meaning  we  shall  not  retain  it. 

As  the  Kegnault  experiments  on  steam  are  always  considered  models 
in  every  respect,  and  as  being  of  unapproachable  accuracy,  we  shall  only 
say  that  they  were  made  in  all  circumstances  and  conditions  in  a  thoroughly 
practical  way,  and  that  the  values  reached  have  been  computed  from  purely 
theoretical  grounds;  so  also  with  densities.  The  table  is  to  be  relied 
upon,  and  we  shall  not  explain  the  experiments  or  comment  further  upon 
them,  but  will  illustrate  by  a  few  examples  the  use  of  the  table  here  given: 


STEAM  MAKING;    OR,  BOILER  PRACTICE. 


TABLE  I.— THE  PROPERTIES  OF  SATURATED  STEAM. 


a-SJi 

v  S  ' 

S.S* 

Mrr 

£  fl 

X  fl  A 

a  S 

*?* 

=3  3 

40^ 

Pressure  in  fib 
per  sq.  inc 
above  the  a 
mosphere. 

Temper  a  tui 
of  steam  1 
degrees  Fal 
renheit. 

Heat  above  3 
F.  in  watt 
at  boilin 
point. 

External  \voi 
in  heat  unit 

0 

i| 

&i 

3si 

H 

\  Internal  woi 
of  evaporat 
in  heat  unit 

Latent  heat  < 
evaporat'ni 
heat  units. 

S-s* 

2  a  • 

:^ 

IfSsg 

£H 

Weight  of  Ic 
ft.  of  stea: 
in  pounds. 

Volume  of  1  i 
in  cubic  fee 

—  14 
—13 

yu 
121 

99 

62 

1109 
1118 

967 

1029 

• 
rt 

0.006 

172.0 

—12 

138 

106 

65 

1124 

943 

1018 

0.008 

117.5 

—11 

150 

118 

67 

1127 

942 

1009 

1 

0.011 

89.6 

—10 

160 

128 

67 

1130 

935 

1002 

3 

.014 

72.6 

—  9 

168 

136 

67 

1133 

925 

993 

£  oj 

.016 

61.2 

—  8 

175 

143 

68 

1134 

923 

991 

.019 

52.9 

—  7 

181 

150 

68 

1137 

918 

987 

>.£ 

.021 

46.7 

—  6 

187 

156 

69 

1138 

913 

982 

11 

.024 

41.8 

—  5 

192 

161 

69 

1140 

909 

979 

$s 

.026 

37.8 

—  4 

196 

165 

70 

1141 

906 

976 

f.2 

.029 

34.6 

<J 

201 

170, 

70 

1143 

903 

973 

Sg 

.031 

31.8 

—  2 

205 

174 

71 

1144 

899 

970 

o 

.034 

29.5 

—  1 

209 

178 

71 

1145 

896 

967 

5 

.036 

27.6 

0 

212 

181 

72 

1146 

893 

965 

1074 

.038 

26.3 

1 

215 

184 

72 

1147 

890 

962 

1074 

.041 

24.3 

2 

219 

188 

72 

1148 

888 

960 

1076 

.043 

23.0 

3 

222 

191 

73 

1149 

887 

958 

1078 

.046 

21.8 

4 

225 

194 

73 

1150 

885 

956 

1079 

.043 

20.7 

5 

227 

196 

73 

1151 

882 

953 

1079 

.050 

19.7 

6 

230 

199 

74 

1152 

879 

951 

1079 

.053 

18.8 

7 

233 

202 

74 

1152 

877 

950 

1079 

.055 

1S.O 

8 

235 

204 

74 

1153 

876 

948 

1079 

.058 

17.2 

9 

237 

206 

74 

1154 

873 

947 

1080 

.060 

16.6 

10 

239 

208 

74 

1154 

872 

945 

1080 

.062 

16.0 

11 

242 

211 

75 

1155 

869 

944 

1080 

.065 

15.4 

12 

244 

213 

75 

1156 

867 

942 

1080 

.067 

14.9 

13 

246 

215 

75 

1156 

866 

941 

1081 

.070 

14.4 

14 

248 

217 

75 

1157 

864 

939 

1081 

.072 

13.9 

15 

250 

220 

75 

1158 

863 

938 

1083 

.074 

13.4 

16 

252 

222 

75 

1158 

862 

937 

1083 

.076 

13.0 

17 

254 

224 

76 

1159 

859 

935 

1084 

.079 

12.7 

18 

256 

226 

76 

1159 

858 

934 

1084 

.081 

12.3 

19 

257 

227 

76 

1160 

857 

933 

1084 

.083 

12.0 

20 

259 

229 

76 

1160 

856 

932 

1085 

.086 

11.6 

22 

262 

232 

76 

1161 

853 

929 

1085 

.090 

11.0 

24 

266 

236 

77 

1162 

850 

927 

*  1086 

.095 

10.6 

26 

269 

239 

77 

1163 

848 

925 

1087 

.099 

10.0 

28 

272 

242 

77 

1164 

846 

923 

1088 

.104 

9.6 

30 

274 

244 

77 

1165 

844 

921 

1088 

.109 

9.2 

35 

281 

251 

78 

1167 

838 

916 

1089 

.120 

8  3 

40 

287 

257 

78 

1169 

834 

912 

1091 

.131 

7.6 

45 

293 

263 

78 

1171 

830 

90S 

1093 

.142 

7.0 

50 

298 

268 

79 

1172 

825 

904 

1093 

.154 

6.6 

55 

303 

273 

79 

1174 

822 

901 

1095 

.165 

6.1 

CO 

307 

278 

79 

1175 

818 

897 

1096 

.176 

5.7 

65 

312 

282 

80 

1176 

814 

894 

1097 

.187 

5.3 

70 

316 

287 

80 

1178 

811 

891 

1098 

.198 

5.0 

75 

320 

291 

80 

1179 

808 

888 

1099 

.209 

4.8 

80 

324 

294 

80 

1180 

806 

886 

1100 

.220 

4.5 

85 

328 

298 

81 

1181 

802 

883 

1100 

.231 

4.3 

90 

331 

301 

81 

1182 

800 

881 

1101 

.241 

4.1 

95 

334 

305 

81 

1183 

798 

878 

1101 

.252 

4.0 

100 

338 

308 

81 

1184 

795 

876 

1102 

,263 

3.8 

NATURE  OF  HEAT  AND  PROPERTIES  OF  STEAM. 


TABLE  I.— THE  PROPERTIES  OF  SATURATED  STEAM. 


«"•§•*• 

2-S.a 

«  *  f? 

•as 

•**&  OB 

*'fl» 

•—•  0)  4J 

ss  a 

6% 

i5I| 

*S6  . 

rt  i|H 

h 

|* 

Ms! 

jTs'S 

||^ 

£IM 

~£ 

|i|i 

|li| 

•isls 

1? 

|£s 

||| 

fe  S 

^P,^ 
fi  JT^g 

•a^-ss 

H 

a  (j 

pll 

lifl 

E-i 

w^' 

Sa 
K-9 

W 

g»i 

M°" 

f  £8 

gi« 

111! 

•Id.  a 

Is 

105 

341 

311 

82 

1185 

792 

874 

1103 

.274 

3.6 

110 

344 

315 

82 

1186 

789 

871 

1104 

.284 

3.5 

115 

34-V 

318 

82 

1187 

787 

869 

1105 

.295 

34 

120 

350 

321 

82 

1188 

785 

867 

1106 

.306 

3.3 

125 

353 

324 

82 

1189 

783 

865 

1107 

.316 

3.2 

130 

355 

327 

82 

1190 

781 

863 

1108 

.327 

3.1 

135 

358 

329 

82 

1191 

779 

861 

1108 

.338 

3.0 

140 

361 

331 

83 

1191 

111 

860 

1109 

.348 

2.9 

145 

363 

334 

83 

1192 

775 

858 

1109 

.359 

2.8 

150 

366 

337 

83 

1193 

773 

856 

1110 

.369 

2.7 

155 

368 

340 

83 

1194 

771 

834 

1111 

.380 

2.6 

160 

371 

341 

83 

1194 

770 

853 

1111 

.390 

2.6 

165 

373 

344 

83 

1195 

768 

851 

1112 

.400 

2.5 

170 

375 

347 

84 

1196 

765 

849 

1112 

.412 

2.4 

175 

377 

348 

84 

1196 

764 

848 

1113 

.422 

2.4 

180 

380 

351 

84 

1197 

762 

846 

1113 

.433 

2.3 

185 

382 

353 

84 

1198 

761 

845 

1114 

.443 

2.3 

195 

386 

357 

84 

1199 

758 

842 

1115 

.463 

2.2 

205 

390 

361 

85 

1200 

754 

839 

1115 

.484 

2.1 

215 

394 

365 

85 

1201 

751 

836 

1116 

.505 

2.0 

225 

397 

368 

85 

1202 

749 

834 

1117 

.525 

1.9 

235 

401 

373 

85 

1204 

746 

831 

1119 

.546 

1.8 

245 

404 

376 

85 

1205 

744 

829 

1120 

.567 

1.8 

255 

408 

380 

85 

1206 

741 

826 

1121 

.587 

1.7 

265 

411 

383 

85 

1207 

739 

824 

1122 

.608 

1.6 

275 

414 

386 

85 

1208 

737 

822 

1123 

.627 

1.6 

285 

417 

389 

86 

1209 

734 

820 

1123 

.649 

1.5 

335 

430 

392 

86 

1213 

725 

811 

1127 

.750 

1.3 

385 

445 

417 

86 

1217 

714 

800 

1131 

.850 

1.2 

435 

457 

428 

87 

1220 

705 

792 

1133 

.950 

1.05 

485 

467 

440 

87 

1224 

697 

784 

1137 

1.049 

0.95 

585 

487 

460 

87 

1230 

683 

770 

1143 

1.245 

0.80 

685 

504 

477 

88 

1235 

670 

758 

1147 

1.439 

0.69 

785 

519 

493 

88 

1240 

659 

747 

1152 

1.632 

0.61 

885 

534 

507 

88 

1244 

649 

737 

1156 

1.823 

0.55 

985 

516 

520 

88 

1248 

640 

728 

1160 

2.014 

0.50 

Values  below  *  *  *  are  computed  and  not  experimental. 

NOTE.— For  all  values  of  Total  Internal  work  below  the  atmosphere  1070  heat  units 
may  be  taken.  All  decimal  parts  of  heat  units  have  been  neglected  and  the  last  one 
may  therefore  be  in  error. 

Example  I. — How  much  more  heat  is  needed  to  boil  a  pound  of  water 
at  200  pounds  per  square  inch  boiler  pressure  than  at  five  pounds  per 
square  inch,  the  feed  being  at  60°  F.  in  either  case. 

AT  FIVE  POUNDS. 

Units. 

Heat  required  to  raise  1  pound  water  from  32°  to  boiling  at  5  pounds  pressure 196 

Deduct  heat  to  raise  from  32°  to  60°  not  used 28 

Heat'  to  raise  from  60°  to  boiling 168 

Internal  work  of  evaporation 882 

External  work  of  evaporation "3 


Heat  required  to  boil  from  feed  at  60°  at  5  pounds. 


.1,123 


STEAM  MAKING;    OR,  BOILER  PRACTICE. 


AT  TWO  HUNDRED  POUNDS. 

Units. 

Heat  required  to  raise  1  pound  water  from  32°  to  boiling  at  200  pounds  per  sq.  inch. .    359 
Deduct  heat  to  raise  from  32°  to  60°  not  used 28 

331 

Internal  work 756 

External  work 84 

1,171 

Heat  required  to  boil  1  pound  of  water  from  feed  at  60°  at  200  pounds: 
1,171  —  1,123  =  48  units. 
48 

=  4  per  cent.,  nearly. 

The  same  result  could  be  reached  more  directly. 

Units. 

Total  heat  from  32°  at  200  pounds 1,199 

Total  heat  from  32°  at  5  pounds 1,161 

Difference 48 

Deducting  from  the  1,151  the  28  units  not  used,  from  32°  to  60°,  the  feed 
being  at  60°,  we  have  1,123  for  the  divisor  to  reduce  to  per  cent,  as  before. 

We  advise  the  reader  to  use  the  former  method,  by  preference,  in  his 
computations,  as  serving  to  keep  in  full  view  the  different  uses  and  the  va- 
rious amounts  of  heat  required  for  them;  although  there  is,  of  course,  more 
numerical  work  required  to  do  so. 

The  reason  so  much  more  difficulty  is  experienced  in  maintaining 
high  pressure  than  low  pressure  steam  is  to  be  found,  not  in  the  boiling  of 
equal  weights  of  water,  but  in  the  fact  that  the  high  pressure  steam 
leaves  the  boiler  more  easily.  If,  for  example,  it  be  employed  in  an 
engine,  the  engine  can  be  made  to  do  more  work  thereby.  If,  in  running 
a  boat,  the  boat  going  faster  the  engine  uses  more  steam;  if  employed 
in  heating  a  building,  the  radiators  act  more  energetically  with  the  higher 
pressure,  transmit  more  heat,  condense  more  steam,  and  the  skillful 
attendant  suits  his  fire  to  the  work. 

Example  II.— How  much  saving  of  fuel  can  be  made  by  raising  the 
temperature  of  the  feed-water  from  100°  F.  to  200°  F.,  the  boiler  pressure 

being  120  pounds  per  square  inch. 

Units. 

Total  heat  for  120  pounds 1,188 

Deduct  in  the  one  case  the  units  not  used  in  raising  the  water  from  32°  F.  to  100°  F . .     68 

Required  from  100°  F.  to  boil  at  120  pounds 1,120 

In  the  other  case  deduct  for  not  using  from  32°  to  200° 169 

Required  to  boil  at  120  pounds  from  water  at  200°  F 1,019 

Difference  between  1,120  and  1,019  is  101  units,  or  about  9  per  cent. 
In  order  to  compare  the  performance  of  different  boilers  working  with 
different  pressures  and  fed  with  water  at  different  temperatures,  it  is  ne- 
cessary to  assume  a  standard  pressure,  temperature  of  evaporation,  and 
temperature  of  feed-water.  Various  temperatures  of  feed-water  have  been 
used,  0°  F.,  32°  F.,  100°  F.,  the  latter  about  the  usual  temperature  of  feed- 
water  for  condensing  engines,  and  212°  F.,  used  more  generally  than  any 
of  the  others  as  a  standard;  while  for  the  pressure  and  temperature  of 
evaporation  the  atmospheric  pressure  and  212°  F.  are  usually  taken. 


NA  TUBE  OF  HE  A  T  AND  PROPERTIES  OF  'STEAM.  9 

Example  III. — By  experiment  with  a  boiler  at  160  pounds  per  square 
inch  it  was  found  that,  one  pound  of  coal  evaporated  7.91  pounds  of  water. 
The  temperature  of  the  feed-water  was  noted  at  120°  F.:  required  the 
equivalent  evaporation  from  and  at  212°  F. 

Units. 

Total  heat  of  evaporation  from  32°  F.  at  160  pounds 1,194 

Deduct  from  32°  to  120°,  units  not  used 88 

Heat  to  evaporate  from  30°  at  160  pounds 1,106 

Internal  heat  of  evaporation  at  212° 893 

External  work  of  evaporation  at  212° 72 

Sum  or  heat  of  evaporation  at  212° 965 


7.91  x  1>106  =  9.06  as  the  evaporation  required. 
965 

In  order  to  facilitate  this  computation  the  following  table  of  factors  of 
evaporation  is  given: 


^    OP  THPJ         ^ 

'UNIVERSITY 


10 


STEAM  MAKING;  OR,  BOILER  PRACTICE. 


•*  OTCOC^C-l^H  rH 


r-IO^lO  O  10  O  10  Ci  -*  C5  •*  C5  CO   OC  CO  X>  CO  t~  01  t-  0-1  t-  C1*  t- 

OOt-t-O    «O  tt  <n  -*  «     MO»C»^-I-H       CCCiC:  X     Xt~t-ttO     »0 


«c  i-iift  o  i«   o  10  o  ko  os   •*  O4  •*  o  co   oo  w  oo  «  t-   <M  t-  <M  t-  i-i    o  I-H  «s  ^H  m   o  m  o  m 
?3M<N?i-4  S  S  5  »  S    xc-t-o--c   «  is  ^  -*  eo   WCI<N^-I^-I    ccrsc--  w   cct-t--^: 


i  « 


f- 


5SSoo   SSoooot--   t-otblnin   -*^cococ4   o-HrHcci    csxxt-t-   S  S  B  S  S   tf! 


^  d    t-C^I^-C^O      rHOi—  i«DO 

oo  ox«-  «  «co^  ^^0  =  5    e  2£  X  E:  t 


CO     OOCOOOCOt-    C^t^C^t^-i—  i    <C»—  'OrHl 

^<    wcocscs,-!   T-I  o  o  g  g.   soxtg 


^  sliis  2SrtS§  ss^^S  sSsSs  Sils 


C^-^CO     COOCOOOC^     tr-C^t"C^ 

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i—  (COrHOO     Iff-OkOOlO 


C^-^C^-^X     COX^t 
t-  t-  «C  O  IO     K5  -*  •* 


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ciCioo    oot-t-oo    ioin-*-*co   cr   ^CNI-IO   ooscixoo   t-t~ec«cio    m  •*  -*  co  so   IM 


gs||     s§2!S  SSasI  lllii  liiil 


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g  s?£s^  isss§  §1S|§         iiiii     S 


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NATURE  OF  HEAT  AND  PROPERTIES  OF  STEAM. 


11 


The  use  of  this  Table  of  Factors  of  Evaporation  is  readily  seen  by  tak- 
ing the  last  example.  The  boiler  evaporating  7.91  pounds  at  160  pounds 
per  square  inch  from  feed  at  120°  F.,  ths  evaporation  factor  from  Table 
II.  for  120°  and  160  pounds  is  1.146.  7.91  x  1.146  =  9.06,  as  before,  for  the 
equivalent  evaporation  from  and  at  212°  F. 

We  introduce  one  other  table  here— the  weight  of  1  cubic  foot  of  water 
at  different  temperatures.  Very  often  in  the  trials  of  a  boiler  or  engine 
the  most  convenient  unit  of  measurement  of  water  is  the  cubic  foot.  This 
will  be  the  case  when  a  weir  measurement  is  made  or  when  the  water  is 
measured  by  a  water  meter.  The  use  of  a  water  meter  involves  many  pre- 
cautions, the  most  important  being  the  following:  The  meter  should  work 
under  moderate  head  of  supply  and  small  head  of  delivery;  it  should  be 
set  in  such  a  manner  that  it  can  be  tested  in  place  under  the  exact  condi- 
tions of  use;  if  a  positive  meter,  it  should  be  especially  constructed  to 
work  freely,  if  it  is  to  be  used  in  warm  water.  This  table  is  also  used  for 
estimating  the  weight  of  water  in  boilers,  and  for  correcting  boiler  trials 
for  differences  of  water  level. 

TABLE    III.— EXPANSION   AND    DENSITY    OF   PURE    WATER. 
FROM  D.  K.  CLAEK  AND  BY  RANKING.  APPROXIMATE  FORMULA. 


Temperature  in  degrees 
Fahrenheit. 

COMPARATIVE. 

Density   of    Weight 
per  Cubic  Foot. 

Volume. 

Density. 

32 

1.00000 

1.00000 

62.418 

35 

1.99993 

.00007 

62.422 

39.1 

1.99989 

.00011 

62.425 

40 

1.99983 

.00011 

62.425 

45 

.      1.99993 

.00007 

62.422 

46 

1.00000 

1.00000 

62.418 

50 

1.00015 

.99985 

62.409 

52.3 

1.00029 

.99971 

62.400 

55 

1.00038 

.99961 

62.394 

60 

1.00074 

.99926 

62.372 

62 

1.00101 

.99899 

62.355 

G5 

1.00119 

.99881 

62.344 

70 

1.00160 

.99832 

62.313 

75 

1.00239 

.99771 

62  .275 

80 

1.00299 

.99702 

62.232 

85 

1.00379 

.99622 

62.182 

90 

1.00459 

.99543 

62.133 

95 

1.00554 

.99449 

62.074 

100 

1.00639 

.99365 

62.022 

105 

1.00739 

.99260 

61.960 

'.10 

1  .00889 

.99199 

61.868 

115 

1.00989 

.99021 

61.807 

120 

1.01139 

.98874 

61.715 

125 

1.01239 

.98808 

61.654 

130 

1.01390 

.98630 

61.563 

135 

1.01539 

.98184 

61.472 

140 

1.01690 

.98339 

61.381 

145 

1.01839 

.98194 

61.291 

150 

1.01989 

.98050 

61.201 

155 

1.02164 

.97802 

61.096 

160 

1.02340 

.97714 

60.991 

165 

1.02589 

.97477 

60.843 

170 

1.02690 

.97380 

60.783 

12 


STEAM  MAKING;    OR,  BOILER  PRACTICE. 


TABLE  III.— CONTINUED. 


Temperature  in  degrees 
Fahrenheit. 

COMPARATIVE. 

Density   of    Weight 
per  Cubic  Foot. 

Volume. 

Density. 

176 
180 

1.02906 
1.03100 

.97193 
.97006 

60.655 
60  .548 

185 

190 
195 
200 
205 

.03300 
.03500 
.03700 
.  03889 
.0414 

.96828 
.96632 
.96440 
.96256 
•  9602 

60.430 
60.314 
60  198 
60.081 
59.93 

210 
212  by  formula. 
212  by  measurement. 

.0434 
.0444 
.0466 

.9584 
.9575 
.9555 

59.  S2 
59.76 
59.64 

230 

250 
270 
290 

.0529 
.0628 
.0727 
.0838 

.9499 
.9411 
.9323 
.9227 

59.36 
58.78 
58.15 
57.59 

298 
338 
366 
390 

.0899 
.1118 
.1301 
.1444 

.9175 
.8994 
.8850 
.8738 

57.27 
56.14 
55.29 
54.54 

The  use  of  the  table  of  the  properties  of  steam  is  more  frequent  in  the 
study  of  engine  performance  and  indicator  diagrams  than  of  boiler  per- 
formance, but  there  is  an  important  point  in  determining  the  evaporation 
of  a  boiler  in  which  it  becomes  of  use. 

As  bubbles  of  steam  formed  on  the  hot  iron  of  a  boiler  rise  through 
the  water  to  the  surface,  breaking  and  scattering  spray,  a  portion  of  water 
thus  thrown  up  into  the  steam  room  is  carried  along  with  the  steam,  and 
unless  more  heat  be  supplied  to  evaporate  this  water  it  increases  the  volume 
caused  by  the  steam  condensed  in  the  pipes  in  the  upper  portion  of  the 
boiler.  This  water  carried  with  the  steam  is  said  to  be  "entrained"  with  it 
and  is  called  "priming"  by  many  writers.  When  the  proportion  of  water 
becomes  so  large  as  to  be  evident  in  the  action  of  the  engine  or  the  exhaust, 
it  is  usually  called  by  engineers  "foaming."  The  amount  of  such  water  is 
increased  if  the  water  is  dirty  and  covered  with  scum,  or  if  grease  and  alkali 
combine  to  form  a  soap.  The  amount  of  water  which  can  be  carried  by 
steam  in  suspension  is  very  great,  but  depends  somewhat  upon  the  velocity 
of  the  current  of  steam;  if  the  passages  are  large,  and  the  flow  of  steam  of 
moderate  velocity  the  water  has  time  to  drop  out  of  the  steam  by  the 
action  of  gravity.  In  some  cases  the  amount  of  water  carried  in  weight 
has  been  known  to  be  three  times  that  of  the  steam  carrying  it,  although 
usually  it  does  not  exceed  10  to  15  per  cent. 

The  higher  the  pressure  of  steam  the  greater  its  density  and  the 
quieter,  other  things  being  equal,  is  the  process  of  ebullition  and  the  smaller 
the  quantity  of  entrained  water.  The  amount  of  water  thrown  up  in  spray 
is  largely  dependent  on  the  circulation,  being  much  diminished  by  im- 
provements in  that  direction.  The  area  of  surface  water  in  contact  with  the 
steam  seems  to  be  an  important  matter  according  to  some  authorities,  but 


NA  TURE  OF  HE  A  T  AND  PROPERTIES  OF  STEAM.  13 

as  this  varies  very  greatly  without  any  apparent  effect,  we  are  not  inclined 
to  attribute  much  importance  to  it.  A  violent  rush  of  steam  close  to  the 
top  of  a  body  of  water  is  to  be  avoided,  as  even  a  current  of  air  would 
throw  spray  in  such  a  case. 

The  accurate  determination  of  the  water  entrained  with  steam  is  a 
matter  of  great  difficulty  and  at  the  same  time  of  great  importance  in  the 
determination  of  the  performance  of  boilers  and  engines. 

Four  methods  have  been  devised  to  measure  the  amount  of  water  en- 
trained, and  two  of  them  have  been  used  in  practice. 

The  first  method,  that  of  M.  G.  A.  Hirn,  is  the  most  used.  It  depends 
upon  the  amount  of  heat  given  out  by  a  known  weight  of  a  mixture  of 
steam  and  water  and  is  best  performed  as  follows: 

A  barrel  is  set  on  a  platform  scale  and  a  known  weight  of  water  run 
into  it.  It  is  convenient  to  put  in  298  Ibs.  of  water.  Steam  is  taken  from 
the  top  of  the  steam  pipe  by  a  rubber  hose  terminated  by  an  iron  pipe 
capped  on  the  lower  end  and  perforated  with  holes  drilled  obliquely  to 
the  radii,  but  in  the  plane  thereof.  This  pipe  is  placed  in  the  barrel  9f 
water  and  steam  turned  on;  the  scale  is  loaded  2  Ibs.  more,  and  as  the 
steam  comes  into  the  water  the  fluid  increases  in  weight,  and  when  the 
beam  tips  there  is  300  Ibs.  of  water.  The  temperature  of  the  water  is  then 
carefully  noted.  The  disposition  of  the  jets  keeps  the  water  stirred  up 
thoroughly,  and  the  flow  of  steam  into  the  water  being  horizontal  only,  the 
water  remains  steady.  The  weight  is  then  increased  10  Ibs.,  and  when  the 
the  scale  tips  at  310  pounds  the  temperature  is  noted. 

The  number  of  heat  units  given  to  the  water,  in  the  barrel,  by  the 
steam  and  water  from  the  boiler,  is  found  by  multiplying  the  300  R>s.  of 
water  by  the  rise  in  its  temperature. 

The  portion  which  was  dry  steam  gives  up  its  internal  heat  of  evapor- 
ation in  condensing,  and  the  external  work  done  by  the  air  upon  the  fluid 
in  compressing  it  from  steam  to  water,  together  make  the  latent  heat  of 
evaporation;  and  the  whole  fluid  then  falls  in  temperature  from  that  due 
to  the  pressure  in  the  boiler  to  the  final  temperature  of  the  barrel. 

Deducting  from  the  heat  gained  by  the  water  in  the  barrel,  ten  times 
the  difference  between  the  boiler  temperature  and  the  final  temperature 
in  the  barrel,  and  dividing  the  remainder  by  ten  times  the  latent  heat  at  the 
boiler  pressure,  the  quotient  will  be  the  fraction  of  the  whole  which  is  dry 
steam. 

It  is  easily  seen  that  with  any  other  weight  the  process  would  be  the 
same;  but  in  place  of  the  ten  we  should  use  the  number  of  pounds  run  in 
between  the  noting  of  the  temperatures. 

The  preliminary  2  Tbs.  is  to  provide  for  any  water  which  might  have 
collected  in  the  hose  or  connections  while  standing,  and  to  render  the  op- 
eration uniform. 

Sometimes  a  coil  of  pipe  as  a  surface  condenser  is  used,  and  the  steam 
which  is  condensed  therein  is  kept  separate  from  the  condensing  water; 
but  great  care  has  to  be  used  to  get  all  the  water  condensed  out  of  the  coil. 
The  accuracy  of  this  method  is  dependent  upon  the  delicacy  of  weighing 


14  STEAM  MAKING;  OR,  BOILER  PRACTICE. 

and  the  reading  of  the  thermometer;  in  unskillful  hands  the  results  are 
sometimes  astonishing. 

The  second  method  is  to  put  into  the  feed  water  a  quantity  of  sulphate 
of  soda,  and  to  draw  from  the  boiler,  at  intervals,  from  the  lower  gauge  cock 
a  small  amount  of  water,  keeping  this  water  by  itself;  also  to  draw  from  the 
steam,  condensing  either  by  a  coil  of  pipe  in  water,  or  a  small  pipe  in  air, 
taking  care  to  draw  only  water  without  steam,  at  the  same  intervals,  keep- 
ing the  one  separate  from  the  other.  A  chemical  analysis  defines  the  pro- 
portion of  sulphate  of  soda  in  each  portion,  and  a  division  of  the  proportion 
of  sulphate  of  soda  in  the  portion  from  the  steam  by  the  proportion  in  that 
from  the  water  gives  the  proportion  of  water  entrained, — the  basis  of  the 
method  being  the  fact  that  steam  does  not  carry  the  sulphate  of  soda, 
this  being  only  carried  by  the  hot  water  entrained.  This  method  was  used 
by  Professor  Stahlschmidt  at  the  Dusseldorf  Exhibition  Boiler  Trials. 

A  third  method  has  been  suggested:  To  enclose  a  portion  of  steam  in  a 
vessel  placed  inside  the  steam  pipe,  then  closing  it  and  removing  it  from 
the  steam  pipe,  obtain  the  weight  of  the  enclosed  fluid,  which,  being 
in  a  known  volume,  the  proportion  of  water  can  be  found  from  the  volume 
and  density  at  the  known  pressure.  There  appear  to  be  many  practical 
difficulties  in  this  method,  and  we  are  not  aware  that  it  has  been  used  to 
any  extent. 

A  fourth  method  is  to  have  a  small  cylinder  with  piston  enclosed  in  the 
steam,  and  to  put  a  known  volume  of  the  cylinder  in  connection  with  the 
steam;  then  closing  the  communication,  pull  out  the  piston  (which, 
of  course,  passes  through  proper  stuffing  boxes  into  the  air)  until  the 
pressure  in  the  cylinder  begins  to  lower, — the  water  contained  evapor- 
ating at  the  pressure,  until,  after  it  has  been  evaporated  the  pressure  begins 
to  fall  with  increase  of  volume.  The  increase  of  volume  at  constant  pres- 
sure divided  by  the  final  volume  is  the  proportion  of  water  carried.  This 
method  promises  well,  but  we  have  no  knowledge  of  its  use. 

Steam  formed  in  the  presence  of  water  is  always  saturated,  that  is,  it  is 
at  the  same  temperature  as  the  water,  and  cannot  be  raised  above  that  tem- 
perature until  the  water  is  all  evaporated;  but  after  this  has  been  done,  or 
if  the  steam  be  heated  in  a  separate  vessel,  the  temperature  rises  nearly 
2°  F.  for  each  unit  of  heat  added  to  a  pound  in  weight,  while  the  steam 
increases  in  volume  at  first  not  very  closely,  but  afterwards  very  nearly  as 
a  perfect  gas,  or  by  4^3  part  of  itself  for  each  degree  F.  The  amount  of 
heat  required  to  raise  1  lb.  weight  of  dry  steam  1°  F.,  is  stated  as  0.47  of  a 
unit,  and  0.5  by  different  authorities,  the  first  including  Eankine,  and  the 
second  Him.  Steam  thus  raised  in  temperature  is  said  to  be  superheated, 
but  our  knowledge  of  this  condition  is  still  very  limited  and  confined  to 
the  results  of  a  few  experiments. 


CHAPTER      II. 

ON  COMBUSTION. 

The  process  of  combustion  is  well  known  to  be  due  to  the  act  of  uniting 
carbon  and  hydrogen  with  oxygen:  other  substances,  such  as  sulphur  and 
phosphorous  also  develop  heat  when  uniting  with  oxygen,  but  for  our 
practical  purposes,  carbon  and  hydrogen  only  need  to  be  considered.  In 
fact,  hydrogen  is  a  very  important  element  in  fuel,  although  forming  but 
a  very  small  part  by  weight  of  ordinary  coal,  the  fuel  most  in  use  as  a 
combustible. 

The  first  question  which  arises  is,  how  much  air  must  be  supplied  to 
our  fuel  in  order  to  produce  complete  combustion,— the  air  being  required 
for  the  oxygen  therein  contained.  The  quantity  of  air  required  varies  with 
the  composition  of  the  fuel,  but  if  we  say  that  for  each  pound  of  fuel  we 
must  supply  twelve  pounds  of  air,  we  shall  be  sufficiently  near  the  truth. 
The  volume  of  air  will,  of  course,  depend  upon  its  temperature.  Now,  the 
quantity  of  heat  which  can  be  developed  by  the  combustion  of  one  pound 
of  pure  carbon,  is  sufficient  to  boil  fifteen  pounds  of  water  from  and  at  a 
temperature  of  212°  F.  if  none  of  the  heat  were  lost;  but  there  are  many 
reasons  why  we  do  not  reach  this  result  in  practice,  and  they  are  as  follows: 

First.— Variations  in  the  quality  of  the  coal  as  to  its  chemical  constitu- 
tion, affecting  thereby  its  calorific  power. 

Second. — Impurities  found  with  and  mixed  in  the  coal,  affecting  the 
actual  quantity  of  pure  coal  in  any  given  amount. 

Third. — Imperfect  or  incomplete  combustion  of  the  fuel. 

Fourth. — Losses  of  heat  from  the  furnace,  the  fire,  and  the  metal  of  the 
boiler. 

Fifth. — The  heat  carried  off  in  the  stack,  more  or  less  utilized  in  the 
creation  of  draft. 

1.  Variations  in  the  Quality  of  FueL—Fiom  the  results  of  chemical 
analyses,  the  evaporative  power  of  various  kinds  of  fuel,  expressed  in 
pounds  of  water  per  pound  of  fuel  evaporated  from  and  at  212°  F.,  which 
we  will  call  E,  have  average  values  which  are  given  in  the  following  table: 

KIND  OF  FUEL. 

E. 

Pure  carbon  completely  burned  to  CO2 15 

Pure  carbon  incompletely  burned  to  CO 4.5 

CO  completely  burned  to  CO2 : 3.9 

Charcoal  from  wood,  dry 14 

Charcoal  from  peat,  dry 12 

Coke  good,  dry 14 

Coke  average,  dry 13  -2 

Coke  poor,  dry 12-3 

Coal,  anthracite I5-3 

Coal,  dry  bituminous,  best 15-9 

Coal ,  bituminous 14< 


16  STEAM  MAKING;   OR,  BOILER  PRACTICE. 

Coal,  caking,  bituminous,  best 16 

Coal,  Illinois,  (from  four  mines  near  St.  Louis) 12 

Lignite 12.1 

Peat,  dry 10 

Peat  with  one-fourth  water 7.5 

Wood,  dry 7.25 

Wood  with  one-fifth  water 5.8 

Wood,  best  dry  pitch  pine 10 

Mineral  oils,  about 22 . 6 

As  to  what  can  be  practically  obtained  under  favorable  conditions,  the 
table  of  Boiler  Trials,  at  the  close  of  this  chapter,  can  answer  for  itself;  and 
in  most  cases,  the  results  given  are  the  best  that  can  be  obtained  with 
clean  boilers  and  skillful  firing.  For  ordinary  service  results  from  75  to  80 
per  cent,  of  those  given  in  the  table  may  safely  be  counted  upon. 

2.  Impurities  in  the  coal  being  earthy  matter,  forms  ashes  in  fires  of 
low  temperature,  and  slag  or  cinders  in  fires  of  high  temperature;  water 
is  also  present  which  has  to  be  evaporated,  forming  steam,  and  even 
decomposing  into  hydrogen  and  oxygen,  thereby  absorbing  heat  which 
passes  off  from  the  furnace;  in  the  latter  case  a  re -combination  may  take 
place,  whereby  the  heat  of  decomposition  is  given  up,  but  that  used  in 
changing  water  into  steam  is  lost  by  being  carried  off  up  the  stack. 

3.  Imperfect  Combustion. — Some  coal  is  usually  lost  with  the  ashes  by 
falling  through  the  grate  bars,  especially  with  such  kinds  of  coal  as 
split  in  the  fire.    In  some  cases  this  is  prevented  by  wetting  the  small  coal, 
thus  holding  it  together  till  when  on  the  fire  it  swells  and  cakes  by  the  heat; 
it  is,  however,  doubtful  if  this  remedy  is  an  economical  one.     The  amount 
of  this  and  the  preceding  loss  may  in  practice  be  inferred  from  the  column 
headed,  Percentage  of  Kefuse  in  the  table  of  Boiler  Trials,  at  the  end  of 
this  chapter. 

From  this  table  it  would  appear  that  the  refuse  is:  For  the  best  soft 
coals  from  3  to  10  per  cent.,  and  for  the  Illinois  coals  from  10  to  20  per  cent. 
From  coal  near  St.  Louis  we  have  usually  found  nearly  12£  per  cent.,  or 
one- eighth.  For  the  anthracites  from  10  to  20  per  cent. 

Taking  all  things  together,  we  find  in  practice  that  the  best  coals  are 
the  English  and  Pittsburgh  soft  coals;  next  in  value  the  anthracites,  which 
are  only  inferior  by  reason  of  their  greater  proportion  of  refuse,  and  the 
results  are  nearly  the  same  for  the  best  soft  coals  and  anthracites.  The 
Illinois  coal  near  St.  Louis  is  80  per  cent,  in  theory,  but  has  rarely  been 
found  in  practice  to  exceed  67  per  cent,  of  the  best  coals. 

Wood  has  about  half  the  evaporative  power  of  coal,  and  the  usual 
comparison  is  to  rate  one  cord,  128  cubic  feet,  equal  to  one  ton  of  coal. 
The  wood  is  supposed  to  be  dry  hard  wood  or  pitch  pine  and  weighs  about 
two  tons.  This  is  the  practice  of  the  master  mechanics  in  this  country  in 
rating  fuel  in  locomotives. 

Indian  corn  has  sometimes  been  burned  and  found  when  dry  to  be 
about  equal  to  the  same  weight  of  wood.  Corn  cobs  have  been  found  to  be 
equal  to  one- third  by  weight  of  Illinois  coal,  or  say  one-fourth  of  good  coal, 
or  one-half  of  good  wood  by  weight. 

Incomplete  combustion  produces  a  very  great  loss,  and  this  is  best 
explained  by  a  quotation  from  Kankine's  Steam  Engine,  p.  270: 


ON  COMBUSTION.  17 


"The  burning  of  carbon  is  always  complete  at  first,  that  is  to  say,  one 
"pound  of  carbon  combines  with  two  and  two-thirds  pounds  of  oxygen,  and 
"makes  three  and  two-thirds  pounds  of  carbonic  acid,  and  although  the 
"carbon  is  solid  immediately  before  the  combustion,  it  passes  during  the 
"combustion  into  the  gaseous  state,  and  the  carbonic  acid  is  gaseous.  This 
"terminates  the  process  when  the  layer  of  carbon  is  not  so  thick  and  the 
"supply  of  air  not  so  small,  but  that  oxygen  in  sufficient  quantity  can  get 
"direct  access  to  all  the  solid  carbon.  The  quantity  of  heat  produced  is 
"14,500  thermal  units,  as  already  stated." 

"But  in  other  cases  part  of  the  solid  carbon  is  not  supplied  directly 
"with  oxygen,  but  is  first  heated  and  then  dissolved  into  the  gaseous  state 
"by  the  hot  carbonic  acid  gas  from  the  other  parts  of  the  furnace.  The 
"three  and  two-thirds  pounds  of  carbonic  acid  from  one  pound  of  carbon 
"are  capable  of  dissolving  an  additional  pound  of  carbon,  making  four  and 
"two-thirds  pounds  of  carbonic  oxide  gas,  and  the  volume  of  this  gas, 
"is  double  that  of  the  carbonic  acid  gas  which  produces  it. " 

"In  this  case  the  heat  produced,  instead  of  being  that  due 
"the  complete  combustion  of  one  pound  of  carbon  =  heat  units.     14,500 
"falls  to  the  amount,   due  to  the  imperfect  combustion  of  two 
"pounds  of  carbon,  or  2  x  4400,  =  heat  units 8,800 


"Showing  a  loss  of  heat  to  the  amount  of 5,700 

"heat  units,  which  disappears  in  volatizing  the  second  pound  of  carbon. 
"Should  the  process  stop  here  as  it  does  in  furnaces  ill  supplied  with  air, 
"the  waste  of  fuel  is  very  great.  But  when  the  four  and  two-thirds 
"pounds  of  carbonic  oxide  gas  containing  two  pounds  of  carbon,  is  mixed 
"with  a  sufficient  supply  of  fresh  air,  it  burns  with  a  blue  flame  combining 
"with  an  additional  two  and  two- thirds  pounds  of  oxygen,  making  seven 
"and  one-third  pounds  of  carbonic  acid  gas,  and  giving  additional  heat  of 
"double  the  amount  due  to  the  combustion  of  one  and  one-third  pounds  of 

"carbonic  oxide.     That  is  to  say,  10,100  x  2  =  heat  units 20,200 

"To  which  add  the  heat  produced  by  the  imperfect  combustion  of 

"two  pounds  of  carbon 8,800 

"There  is  obtained  the  heat  due  to  the  complete  combustion  of  two 
"pounds  of  carbon  2  x  14,500  =  heat  units 29,000 

With  coal  that  has  little  flame,  a  thin  fire,  with  exactly  the  right  draft, 
has  been  found  to  give  the  best  results,  producing  exactly  the  effects  in  the 
first  part  of  the  quotation. 

It  may  be  doubted  if  such  a  bad  state  of  affairs  is  often  found  in  a 
boiler  furnace  of  the  present  day  as  indicated  in  the  middle  of  the 
quotation,  though  a  tendency  to  an  insufficient  supply  of  air  may  exist  in 
internally  fired  boilers,  such  as  locomotives,  if  there  is  a  very  thick  fire 
and  no  air  admitted  above  the  grate;  and,  although  not  approaching 
remotely  the  case  when  no  carbonic  acid  is  produced,  some  of  the  carbonic 
oxide  may  pass  off  unburned.  In  such  cases  the  admission  of  air  above  the 
fuel  will  be  found  beneficial. 


18  STEAM  MAKING;    OK,  BOILER  PRACTICE. 

In  all  soft  coals  there  are  found  compounds  of  carbon  and  hydrogen 
known  as  hydro-carbons,  which  must  also  pass  into  the  gaseous  condition 
before  being  burned.  "If  these  hydro -carbons  such  as  pitch,  tar,  naptha 
"etc.,  are  mixed  on  first  issuing  from  the  coal  with  a  large  quantity  of  air, 
"these  inflammable  gases  are  completely  burned  with  a  transparent  blue 
"flame,  producing  carbonic  acid  and  steam,  but  if  raised  to  a  red  iieat 
"before  being  mixed  with  air  enough  they  disengage  carbon  in  fine  powder 
"and  the  higher  the  temperature  the  more  carbon  they  disengage.  If  this 
"disengaged  carbon  is  cooled  below  the  temperature  of  ignition  before 
"coming  in  contact  with  oxygen  it  constitutes  while  floating  in  gas  smoke, 
"and  when  deposited  on  solid  bodies  is  soot.  But  if  this  disengaged 
"carbon  is  maintained  at  the  temperature  of  ignition,  and  supplied  with 
"oxygen  sufficient  for  its  combustion,  it  burns  while  floating  in  the  inflam- 
"mable  gas  with  a  red,  yellow,  or  white  flame.  The  flame  from  fuel  is  the 
"larger  the  more  slowly  its  combustion  is  effected,"  and  with  the  colors 
of  flame  given  above  as  the  combustion  of  smoke  is  less  or  more  complete. 
An  example  of  this  is  found  in  the  use  of  common  illuminating  gas  when 
burned  with  a  "Bunsen"  or  a  common  burner.  The  chilling  of  the  gaseous 
hydro-carbons,  which  are  driven  off  from  the  solid  pieces  of  coal  by  the 
heat  developed,  may  take  place  in  two  ways:  either  by  coming  into  contact 
with  a  cold  body  as  the  iron  of  the  boiler,  or  by  finding  too  much  cold  air 
in  the  furnace.  To  fully  sustain  the  latter  statement  only  a  little  consid- 
eration need  be  given  to  some  of  the  fundamental  principles  of  heat.  It  is 
well  known  that,  if  a  certain  amount  of  heat  communicated  to  a  body  of 
certain  weight  and  givenlmaterial  raises  its  temperature  a  definite  number 
of  degrees  thereby,  the  same  amount  of  heat  communicated  to  twice  the 
weight  of  the  same  material  will  only  raise  its  temperature  one-half  the 
number  of  degrees  that  it  was  in  the  first  case. 

To  apply  this  to  combustion:  One  pound  of  carbon  burned  with 
twelve  pounds  of  air  gives  thirteen  pounds  of  gas  at  a  temperature 
of  45800  F.  above  that  of  the  external  air;  but  it  is  found  that  this 
rarely,  if  ever,  happens,  and  that  to  supply  oxygen  in  plenty  to  the  hot 
carbon  surrounded  by  gas  from  50  to  100  per  cent,  more  air  is  used,  and 
the  result  is  from  nineteen  pounds  of  gas  at  a  temperature  of  35115°  F. 
to  twenty-five  pounds  of  gas  at  a  temperature  of  2440°  F.  above  the 
external  air;  but  if  forty- eight  pounds  of  air  per  pound  of  coal  were 
admitted,  the  resulting  temperature  of  the  forty-nine  pounds  of  gas 
would  be  about  1250°  F.  above  the  external  air.  With  anthracite  coal  and 
coke,  such  a  lowering  of  temperature  is  not  accompanied  by  serious  loss, 
but  with  bituminous  and  semi-bituminous  coals,  such  a  reduction  of  the 
temperature  of  the  fire  is  always  productive  of  great  waste. 

To  examine  this  more  closely,  suppose  a  coal  with  one-half  free  carbon 
and  one-half  hydro-carbon  set  on  fire  by  the  heat.  If  such  a  coal  were 
burned  with  twelve  pounds  of  air  per  pound  of  coal  the  temperature  of  the 
gas  before  the  hydro-  carbon  ignited  would  be  2440°  above  the  air,  and  the 
hydro- carbon  would  burn  if  supplied  with  oxygen  enough  and  complete 
the  combustion.  Now  if  we  burn  this  coal  with  twenty-four  pounds  of  air 


ON  COMBUSTION. 


per  pound  of  coal,  we  have  only  about  1300°  F.,  as  temperature  of  the 
smoky  product,  and  it  is  a  question  whether  the  gas  would  ignite;  while 
with  more  air  than  this  a  great  proportion  of  the  gaseous  fuel  is  lost  and 
other  evils  are  incurred. 

We  find  then  one  marked  point  of  difference  between  the  anthracite 
and  soft  coals  as  fuel.  While  the  former  burns  completely  with  a  thin  fire 
admitting  an  excess  of  air  through  it,  and  the  free  quantity  of  heat  is 
developed,  though  the  resulting  temperature  is  not  very  high,  the  soft 
coal,  on  the  contrary,  absolutely  requires  for  perfect  combustion  a  high 
temperature  and  plenty  of  room  before  coining  in  contact  with  the  iron  of 
the  boiler,  and  any  deviation  from  these  conditions  produces  smoke  and 
great  loss  of  heating  power;  and  that  while  with  hard  coal  too  great  a 
draft  only  wastes  a  small  quantity  of  heat  in  the  stack,  with  soft  coal  too 
great  a  draft  may  be  as  bad,  or  even  worse,  in  its  effects  than  too  little. 

With  soft  coal  the  required  high  temperature  over  the  fire  may  be 
produced  by  intercepting  the  radiant  heat  of  the  fire  by  a  fire  brick  arch 
or  dome,  which  radiates  back  again  to  the  fire,  heating  the  products  of 
combustion  from  both  sides;  this  was  first  introduced  by  Mr.  C.  Wye 
Williams  many  years  ago,  and  has  been  frequently  revived  in  different 
forms  since.  In  some  devices  air  is  introduced  at  the  bridge,  or  at  the 
edges  of  the  arch  or  dome. 

The  great  trouble  with  such  arrangements  has  always  been  the  lack 
of  durability  of  the  brick,  used  in  .the  arch  or  dome.  In  fact,  the  more 
refractory  the  material  the  hotter  the  fire,  and  the  destruction  of  the  arch 
becomes  only  a  question  of,  what  is  comparatively,  a  short  time. 

One  of  the  satisfactory  ways  of  obtaining  a  high  temperature  is  by 
using  so  thick  a  bed  of  coal  that  the  passage  of  too  great  a  quantity  of  air 
is  prevented  by  its  friction  upon  the  fuel:  the  thickness  of  fire  being 
regulated  by  the  size  of  the  coal  used,  and  kept  so  that  it  will  not  clinker 
too  much.  This  effectually  raises  the  temperature  of  the  fire;  it  may 
also  be  done  by  the  use  of  a  damper,  but  not  in  so  satisfactory  a  manner, 
although  there  is  found  to  be  in  many  cases  a  marked  improvement  by  de- 
crease in  the  draft.  The  general  opinion  in  this  country  is  decidedly  in 
favor  of  thin  fires,  and  the  experiments  of  Professor  Johnson  at  Washington 
favor  this  practice;  but  the  experiments  at  Wigan,  England,  gave  generally 
"the  thicker  the  fire  the  better  the  result."  Experiments  with  a  pyrometer 
are  needed  in  each  case,  but  we  may  safely  say  that  great  improvement  can 
be  made  in  our  practice  in  this  respect,  and  that,  the  only  secret  in  smoke 
prevention  is  to  have  a  hot  fire  with  room  and  time  to  let  all  the  gas  burn 
before  coming  to  less  than  a  red  heat,  and  to  fire  in  small  quantities  over  a 
part  of  the  grate  at  one  time  only. 

Losses  of  heat  by  radiation  and  conduction  from  the  furnace  and  ash 
pit  of  externally  fired  boilers  are  to  be  provided  against  by  making  the 
walls,  if  of  brick,  in  two  thicknesses  with  an  air  space  between  them;  by 
keeping  the  ash  pit  doors  partially  closed,  and  by  covering  all  radiating 
surfaces  of  metal  with  some  good  non-conducting  material,  such  as  thick 
felt  faced  on  the  inside  with  one -quarter  inch  of  asbestos. 


20  STEAM  MAKING;    OR,  BOILER  PRACTICE. 

The  amount  of  heat  which  may  be  lost  by  radiation  from  uncovered 
iron  surfaces,  exposed  to  air  on  one  side  and  steam  on  the  other,  may  be 
estimated  as  two  and  six-tenths  heat  units  per  square  foot  per  hour  per 
degree  F.  of  difference  of  temperature  between  the  steam  and  the  air.  If 
the  air  in  the  room  be  still,  this  amount  may  not  be  reached,  but  if  exposed 
to  violent  winds  it  may  be  exceeded. 

The  heat  passing  up  the  chimney  is  not  wholly  lost,  but  is  use- 
ful in  producing  a  draft;  and  it  can  be  shown  that  in  a  chimney  where  the 
draft  is  produced  by  the  excess  of  weight  of  the  outside  air  over  that  of  the 
hot  gns  in  the  chimney,  that  the  greatest  quantity  of  gas  by  weight 
will  pass  up  the  chimney  when  the  temperature  of  the  gas  in  the  chimney  is 
about  6-25°F.  hotter  than  the  external  air.  With  higher  temperatures  the  vel- 
ocity of  flow  will  be  greater  and  the  quantity  of  gas  by  weight  will  be  less  o  w  - 
ing  to  its  greater  volume.  Looked  at  as  a  means  of  burning  coal  for  making 
steam,  the  most  coal  that  can  be  burned  to  advantage  in  a  given  time  in  a 
boiler  furnace  is  when  the  temperature  in  the  stack  is  near,  but  does  not 
exceed,  that  of  melting  lead.  A  higher  temperature  than  this  means  that 
the  heat  has  not  been  properly  taken  out  of  the  gas,  and  points  to  an  in- 
crease in  the  boiler  surface  as  a  means  of  improving  the  performance  of  the 
boiler  and  increasing  the  yield  of  steam,  as  well  as  the  economj7  of  its  pro- 
duction; a  less  temperature  than  the  above  is  always  desirable  if  the 
required  quantity  of  steam  can  be  maintained.  In  case  twenty-  four  pounds 
of  air  per  pound  of  fuel  is  used  the  temperature  of  stack  giving  maximum 
quantity  of  coal  burned  requires  a  little  more  than  one-fourth  of  the  heat 
generated  to  maintain  the  draft  and  the  other  three-quarters  should  pass 
into  the  water  of  the  boiler.  If  we  could  get  along  with  only  twelve  pounds 
of  air  per  pound  of  fuel,  only  one-eighth  of  the  heat  generated  would  be 
required  to  maintain  maximum  draft.  With  forty-  eight  pounds  of  air  per 
pound  of  fuel,  one-half  of  the  heat  generated  Avould  be  used  in  maintaining 
maximum  draft.  Here  again  the  importance  of  hot  fires  is  plainly  indica- 
ted, and  there  is  yet  another  reason  for  them:  with  a  hot  fire  more  of  the 
heat  generated  passes  into  the  water  near  the  fire,  leaving  the  products  of 
combustion  at  a  lower  temperature  to  traverse  the  remainder  of  the  surface 
and  to  leave  the  boiler  at  a  lower  temperature.  More  of  the  heat  generated 
is  therefore  utilized  than  when  the  fire  is  not  so  hot. 

A  simple  relation  between  the  height  of  the  stack  in  feet  above  the 
grate,  its  area  in  square  feet,  and  the  number  of  pounds  of  coal  per  minute 
burned,  is  the  following  equation,  where: 

h  =  height  in  feet  of  the  stack. 

A  =  area  in  square  feet  of  stack. 

F  =  number  of  pounds  of  coal  burned  per  minute. 


It  is  understood,  however,  that  A  is  the  "least  flue  area"  in  the  passage 
of  the  hot  gas. 


ON  COMBUSTION. 


The  effects  of  changing  the  flue  area,  or  as  it  is  called  the  "calorimeter," 
and  the  proportions  of  heating  surface  and  calorimeter  to  grate  area  are 
seen  in  the  table  of  boiler  trials  following. 

Gas  has  been  employed  as  a  fuel  in  boiler  furnaces  to  a  limited  extent 
and  for  some  years  past,  principally  in  Europe;  but  the  knowledge  of  its 
adaptability,  cleanliness,  and  heating  qualities  becoming  wider,  coupled 
with  the  discoveries  of  large  reservoirs  of  natural  gas  in  certain  districts, 
has  called  closer  attention  to  gas  as  a  fuel  and  its  use  is  largely  extending. 
As  data  on  this  subject  is  limited,  consequent  upon  the  little  knowledge 
extant  of  the  results  of  the  use  of  gaseous  fuel,  we  do  not  consider  it  advis- 
able to  embody  it  in  this  work.  In  general  cases  there  seems  to  be  little 
chance  of  gain  with  properly  constructed  furnaces  and  with  boilers  of 
sufficient  extent  of  heating  surface  to  pay  for  the  apparatus,  simple  as  it 
is,  of  a  producer. 

The  following  tables,  from  page  22  to  page  46,  inclusive,  give  results 
of  a  large  number  of  boiler  trials,  and  need  no  further  explanation. 


UNIVERSITY 


22 


STEAM  MAKING;  OR,  BOILEll  PJiACTlGE. 


|8 
§£ 
» 


3 

4 
5 
6 
7 
8 
9 
10J 

11 
12 

13 
14 
15 

16 
17 
18 
19 
20 
21 
22 
23 

24 
25 
26 

27 
28 
29 
30 
31 
32 
33 
34 
35 

36 

37 

38 
39 

40 
41 
42 

43 

44 

45 
46 

47 
48 
49 

50 
51 
52 
53 
54 
55 

56 


AUTHORITY. 

LOCATION. 

KIND  OF  BOILER. 

KIND   OF  FUEL.    '£ 

2=2 
6 

Water  heating  sur- 
face in  sq.  ft. 

F.  Isherwood.  .  . 

!:: 

it 
it 

"          ... 

Brooklyn  W.  W 

Return  drop  flue  
Return  water  tube  

Anthracite  .... 
Ormsby  

112.5 
90 

100 

;m 

47 
84 
79 

40 
41 

59 

it 
76 
47 
S 

it 
36 

" 

4518 
2690 

ii 
it 

2703 
11852 
1484 
1955 
2374 

954 
1051 

1993 

1818 

981 
1144 

952 

856 
760 

928 
820 
712 

1144 

ii 

" 

U   S.  S.  Michigan  

it 

it 

14              

11 

[4 

Cl 

11 

II 

II 

II 

|| 

" 

II 

U 

u       

" 

It 

II 

Brookfleld... 
Anthracite  

Semi-Bit 

" 

II 

U.  S    S    Penguin 

Return  flue  N.  River  type. 

Rfitnrn  watpr  t.nhp 

U.  S.  S.  Roanoke 

U.  S.  S.  Jacob  Bell  1  N.  River. 

U.  S.  S.  Bibb  2  N.  River  
U.  S.  S.  Mt.  Vernon  i  N.  Riv«r 

U.  S.S.  Valley  City  
U.  S.  S.  Crusader  

Anthracite  

it 

i 

it 

it 
Semi-Bit.!!!!! 

U.  S.  S.  Wyandotte 

Return  water  tube  

t 

i                                                              

' 

t 

l  N.  River        

i 

U  .  S  .  S.  Underwriter  

U.  S.  S.  Young  America.. 
Navy  Yard,  N.  Y... 

Anthracite  .  . 
Semi-Bit 

it 

Anthracite  .... 

Return  fire  tube  

tt 

" 

ii 

ii 

M 

« 

II 

it 

(1 

u 

II 

it 

II 

,,               

II 

11 

Lackawanna  .  . 

Scranton  
Boston  
Hazelton  
Pittston 

ii 

II 

•' 

U 

it 

It 

,i 

II 



11 

II 

it 

1C 

ii 

u 

11 

II 

" 

II 

Council  Ridge. 

ON  COMBUSTION. 


23 


Steam  heating  sur-  j 
face  in  sq.  ft.  j 

a 
| 

i 

o 

°£ 

?*  Height  of  chim- 
5'  ney. 

Water  heating  sur- 
face -T-  grate  area. 

Steam  heating  sur- 
face -r-  grate  area. 

+3 
'I' 

Grate  area  -r-  chim- 
ney area. 

85 

18.9    12.6 

100 

40 

0.9 

5.95 
3.21 

8.95 

6.34 
" 

28.3 

14.19 

45 

29.9 

M 

M 

M 

M 

» 

» 

« 

" 

" 

« 

» 

'• 

" 

» 

" 

" 

" 

'• 

M 

ii 

? 

" 

„ 

« 

" 

it 

» 

» 

!! 

.' 

" 

'  i 

262 

'i83 
110 

276 

180 

13.5 
53.5 
6.1 
10.8 
12.4 

16.8 
50.3 
7.0 
11.0 
12.6 

51.6 
61 
50 
38.7 
55 

r 

31.4 
23.2 
30.1 

,„ 

"i" 
1.4 

5.2 

7.32 
6.32 

7.7 
8.0 
6  » 

8.2 

8.1 

7.7 
12.8 

5.;4 

5.95 
6.73 
6.7 
7.6 
6;3 

4;6 
5;8 

4.9 

8.7 

34 

23.8 

4.5 

8.6 

'327 
37 

5.1 

7.1 

43.5 

25.6 

2.1 

10.0 

9.^6 

50.9 

17.51 

sf.a 

" 
'  Vi  ' 

" 

« 

•• 

" 

'   i 

« 

« 

" 

« 

•I 

•• 

12.5 

6  0 
6.2 

12.6 

52 

23.9 

4.0 

9.5      0.0 

7.9 

47 
72 

20.8 
31.8 

0.3 

7.8      6.0 
5.8       " 

" 

4.8 

u         " 

26.4 

M 

7.5 

» 

,, 

4.1 

„ 

„ 

23.4 

" 

8.8 

M 

3.4 

<. 

21.1  j    " 

10.5        " 

;; 

4.6 
3.8 
3.1 

6.2 

« 

• 

25.8 
22.8 
19.8 

31;8 
it 

" 

7.8 
9.4 
11.7 

5;8 

CC 

i    " 

: 

_^ 

EVAPOBA- 

=M 

T'N  FBOM 

H 

tg 

i 

&  \.T  212°. 

1 

II 

I  !l 

SB 

ft 

KEMABKS. 

0  0) 

-4-3          03  o 

§  § 

_O 

.  « 

«            .  p 

•£ 

n 

JbC 

a  ^£ 

j§~ 

E 

^           PH    |   nJ"- 

J     i       ft 

13.3        Hi     9.4 

10.6         42 

13.5        11      9.3 

10.5 

43 

13.5  j 

8.3 

8.9 

72 

11.4 

8.2 

10.1 

M 

9.5 

9.1 

9.8 

" 

6.3 

9.8 

10.2 

" 

5.2 

10.1 

10.8 

" 

3.8 

9.4 

9.9 

** 

4.1 

8.8 

9.4 

" 

4.4      6.0 

9.4 

10.0 

296 

7.8 

6.2 

9.1 

9.7i       288 

12.2 

5.5 

9.0 

9.5 

252 

22.9 

5.0 

8.8 

9.3 

72 

18.5 

6.8 

8.3 

8.9 

72 

11.4 

18.5 

8.2 

10.1 

72 

11.9 

23.3 

8.7 

11.4 

72 

(  1  only  in  4  used  in  experi- 

7.0 

18.4 

1C.  6 

13.0 

72 

)     ment. 

11.4 

14.2 

10.4 

12.1 

72 

11.0 

21.8 

8.1 

10.3 

72 

11.7 

10.0 

9.5 

10.5 

49 

11.5 

15.0 

9.3 

10.9 

48 

11.0 

17.0 

9.4 

11.3 

48 

12.0 

12.5 

10.0 

11.5 

48 

10.7 

8.7 

10.3 

11.8 

96 

12.9 

15.8 

9.4 

11.2 

48 

12.9 

19.8 

9.0 

11.2 

48 

9.0 

19.9 

11.5 

12.9 

72 

8.2 

13.1 

12.0 

13.9 

16 

7.9 

11.9 

11.6 

13.1 

" 

11.6 

10.9 

11.1 

12.4 

'  fc 

10.4 

13.1 

10.4 

12.0 

'* 

11.6 

11.6 

10.3 

11.7 

11.7 

8.7 

10.5 

11.5 

" 

11.2 

11.4 

10.0 

11.3 

48 

11.0 

13.2 

10.7  |12.4 

24 

11.3 

17.2 

8.7    10.5 

72 

12.3 

14.2 

8.8 

10.2 

72 

9  rows  tubes. 

11.6 

16.8 

8.4 

10.1 

fct 

18  in  a  row,  horizontal. 

13.9 

17.3 

9.3    11.3 

" 

13.3 
12.4 

17.3 
20.0 

8.9 
8.3 

10.8 
10.4 

24      '2  upper  rows  stop. 
48       2  lower  rows  stop. 

11.9 

13.9 

8.5 

9.9 

" 

2  lower  rows  stop. 

9.8 
13.1 

17.3 
16.3 

9.8 
9.4 

11.8 
11.3 

50 

48 

3  upper  rows  stop. 
3  lower  rows  stop. 

10.5 
12.9 

is.  r 

17.1 

9.9 
9.6 

12.1 
11.6 

48 

48 

4  upper  rows  stop. 
4  lower  rows  stop. 

12.4 

19.1 

8.5 

10.5 

48 

2  vertical  rows  stop. 

13.2 
12.8 

14.0 
16.9 

9.4 
9.3 

10.9 
11.2 

3  vertical  rows  stop. 
4  vertical  rows  stop. 

12.6    17.5 

9.2 

11.2 

73 

Anthracite. 

12.7    17.0 

9.1 

10.9 

'' 

12.2  117.2 

8.4 

10.1 

'* 

12.6  J20.9 

8.8 

11  1 

13.0    15.0 

8.9 

10.4 

12.3    17.4 

8.6 

10.5i 

12.6  J10.8 

9.7 

10.8 

24 


STEAM  MAKING;    OK..  B01LEK  PRACTICE. 


Number  for  Refer- 
ence. 

AUTHORITY. 

LOCATION. 

KIND  OF  BOILEK. 

i  <u           • 
C          si 

§    :  § 

«       *g 
a     \  M  . 

KIND  OF  FUEL.    '£           ts  $ 

<U         i      0)     " 

&  .  '•  *a 

2^:    |g 

g£  !  "«  a 

o      tr 

57 
58 
59 
60 
61 

62 
63 
64 
65 
65 
€6 
67 

68 
69 
70 
71 
72 

73 

74 
75 
76 

77 
78 
79 
80 
81 

82 
83 
84 

P5 
86 

87 
88 
89 
90 

91 
92 
93 
94 
95 

96 

97 
98 

66 
67 
68 
69 

70 

71 
72 
73 

74 

75 

76 
77 

78 

B.  F.  Ishcrwood.  .  . 

NavvYard,  N.  Y  

Return  fire  tube  Spring  Mt  
Locust  Mt  
Unknown  .  . 

36 

84 
107 
200 

80 
62 

Ct 

84 

65 

48 
101 

108 

M 

44 
32 
56 
50 

49 

1144 

2506 

3528 
503fc 

2101 

M 

2023 

2565 

1360 

1409 
3375 

2664 

it 
ii 
2332 

1196 
693 
1528 
1199 

1198 

H 

II 
M 

U 

(I 

M 
U 

It 

II 

M 
If 

U 

II 

Broad  Mt  
Black  Heath  .  . 

Broad  Top  
Cumberland.  .  . 
Eagleton  
Glen  Carbon.  .  . 
Anthracite 

« 



"                                        ! 

« 

2  Return  fire  tube 

<c 

U.  S.  8.(Monitor  

U.  S    Passaic 

2  Return  water  tube  

U.  S.  Mackinaw  

M 

*' 

U.  S.  S.^Eutaw  



„              

„                               

U 

II 

J,               

l« 

" 

U.  S.  S.  Gov.  Buckingham 
U.  S.  S.  Daylight  

1  N.  River  .... 

1  N.  River  

U.  S.  S.  Shockokon  

H 

«* 

U.  S.  S.  Mahaska... 

Return  water  tube  

U.  S.  S.  Maratanza...... 
U.  S.  S.  SanJacinto.. 

Fire  tube  

M 

1. 

" 

M 

K 
it 

It 

I  Return  water  tube 

U.  S.  S.  Satellite  ... 
U.  S.  S.  Zouave  

1  N.  River  

U.  S.  S.  Com.  Barnev.... 
U.  S.  8.  Ella 

" 

" 

H 
M 

U.  S.  S.  Miami  

Return  fire  tube  

......::. 

ON  COMBUSTION. 


25 


Steam  heating  sur-  i 
face  in  sq.  ft. 

a 

es 

<U 
& 

««• 

Id- 
r 

1 

CJ 

°z 

|£ 

Height  of  chim- 
ney. 

Water  heating  sur- 

t 
3 
j 
j 
i 

~i 

) 
\ 

Steam  heating  sur- 
face -i-  grate  area. 

Grate  area  -r-  least 
flue  area. 

Grate  area  -f-  chim- 
ney area 

Lbs.  coal  per  sq.  it. 
grate  per  hour. 

Per  cent  refuse. 

E  VAPOR  A  - 
T'N  FKOM 
&  AT  212°. 

Duration  in  hours. 

f! 
# 

Is 
gs 

»* 

3* 

ft.  in. 

37 

6.2 

7.9 

72 

31.8 

0.3    5.8 

6.0 

11.1 

12.7 
12.3 
11.9 
13.9 

10.9 
11.0 
12.4 
14.0 
6.0 
5.2 
5.4 

4.5 

13.8 
19.7 
14.1 
19.4 
17.3 

13.9 
8.4 
13.0 
17.7 
24.9 
23.4 
15.9 

19  8 

9.2 
8.7 
8.8 
8.2 
9.3 

10.0 
10.2 
9.3 
9.2 
9.6 
9.5 
11.0 

10.9 

10.6 
10.8 
10.2 
10.2 
1.3 

1.6 
11.2 
10.7 
1.2 
12.8 
2.4 
13.0 

3  6 

73 

72 
33 
55 

t8 
72 

48 

72 

48 

72 

" 

M 

48 

*fc 

*      ! 

" 

i- 

K 

;; 

« 

;;!   » 

» 

747.94 

5.4      42.5 

26.5 

0.812.0 

17.5 

35'l3.3 

171  26.7 

8.7 
23.8 

27 
58.5 

32.9 
25.2 

0.3    8.0 

0.8!   7.5 

12.3 
8,4 

•  i        ti 

" 

« 

M 

I!  :     \\ 

2,7 

6.3 

6.3 
5.3 
4.5 

8.4 
13.8 
13.8 
12.8 

4.8 
5.3 
8.5 
7.6 
9.8 

13.1 
10.4 
9.4 

8.2 
10.4 

17.4 
10.1 
6.7 
9.6 

5.0 
12.6 
10.9 
12.1 
11.3 

24.6 
23.3 
22.5 

11.6 
11.2 
12.3 
10.5 

23.7 

12.8 
11.3 
13.4 
11.7 

17.5 

17.7 
18.0 

18.3 
22.7 
17.6 
20.0 

19.1 
15.5 
20.7 
23.2 

24.0 
23.8 
21.6 
24.0 
23.1 

16.7 
16.2 
16.0 

20.4 
20.4 

12.5 
12.5 
17.4 
26.2 

14.0 
14.3 
19.0 
18.2 
19.9 

14.8 
16.0 
16.6 

14.5 
18.0 
17.9 
20.4 

16.3 

18.1 
18.0 
12.1 
21.0 

19.4 
19.8 
18.3 

11    r 

10.1 
9.7 
10.6 
10.7 

10.4 
9.4 
9.5 
7.4 

9.3 

9.4 
10.2 
9.5 
9.7 

9.0 
8.7 
9.0 

8.9 
9.4 

7.5 
7.5 
11.5 
9.7 

9.9 
8.9 
9.5 
9.5 
9.9 

6.6 
7.0 
6.8 

10.8 
10.6 
10.2 
10.7 

7.3 

8.7 
9.6 
9.1 
8.8 

9.0 
8.9 
8.9 

o  a 

2.4 
12.5 
2.8 
13.4 

12.8 
11.1 
12.0 
9.7 

12.2 
12.3 
13.1 
12.5 
12.6 

10.8 
10.4 
10.7 

11.2 
11.9 

8.5 
8.5 
13.9 
13.1 

11.5 
10.4 
11.7 
11.6 
12.4 

7.7 
8.3 
8.1 

12.7 
12.9 
12.4 
12.4 

8.7 

10.6 
11.7 
10.3 
11.1 
11.2 
11.1 
10.8 
in  n 

u 

210 

10.1 

n.(9 

;; 

as. 

J 

3 

3^4 

M 

5.9 

;; 

M 

li 

K 

K 

10.4 

23.0 

44 

w. 

" 

110 
195 

7.0 

8.3 

43.6 

30.4 

1.3 

12.0 

10.2 

7.4 

13.6 

55.9 

21. 

1 

3.0 

8.8 

4.7 

47 
190 

448 

6.5 

15.6 

164S 

it 

7.9 
14.2 

31,5 

59.6 
60.6 

51.6 

29.3 
33.5 

24.J 

1.0 
1.9 

7.4 
6.4 

6.^5 

6.0 
7.1 

6.8 

M 

" 

" 

" 

" 

' 

16.9 

11 

51.5 

30. 

5 

4.1 

6.4 

6.9 

'• 
" 

8.1 
10.3 

7.S 
9.2 

7.C 

212 
32 
231 
152 

48 

,, 

5.0 
2.5 
6.3 
5.3 

6.9 

7.1 
3.1 
8.7 
5.1 

7.1 

49.2 
33.7 
50.0 
51.5 

50 

27.3 
121.3 
27.3 
24.2 

24.2 

" 

4.8 
1.0 
4.1 
3.1 

1.0 

8.7 
12.8 
8.9 
9.8 

7.1 

it 

|; 

« 

" 

» 

'" 

» 

" 

REMARKS. 


Semi-  bitumi  nous. 
Semi  -  bituminous. 
Bituminous. 
Bituminous. 


4/5  part  of  one  of  two  used, 
No.  73  natural  draft,  others 
steam  jet. 


With  natural  draft  1/6  only  of 
boiler  for  No.  91. 


With  blower. 

Natural  draft. 

j 

j 

Fan  draft. 


26 


STEAM  MAKING;    07?,  BOlLEli  PRACTICE. 


Number  for  Refer- 
ence. 

AUTHORITY. 

LOCATION. 

KIND  OF  BOILEB. 

KIND   OF  FUEL. 

o* 

CO 

a 

f. 

Water  heating  sur- 
face in  sq.  ft. 

79 

B.  F.  Isherwood... 

U.   S.   S.  Miami  

Return  fire  tube 

Anthracite 

49 

1198 

80 

81 

t«. 

t< 

44 

i> 

tt 

tt 

8? 

" 

" 

H 

u 

tt 

tt 

83 

M 

M 

It 

,t 

„ 

„ 

84 

" 

tt 

II 

M 

tt 

tt 

85 

" 

" 

•  ' 

" 

tt 

tt 

86 

tt 

tt 

II 

M 

ti 

tt 

87 

" 

" 

II 

H 

tt 

it 

88 

II 

U    S   S  Philadelphia 

U 

M 

117 

2941 

89 
90 

ct 

U.  S.  S.  Dragon  
U.  S.  S.  Gen.  Putnam  

N.  River  .. 

•  (                

34 
44 

1007 
1118 

91 

M 

U.  S.  S.  Whitehead  

Return  drop  flue  

II 

37 

1038 

9? 

M 

U.  S.  S.  Morse  

(i 

56 

1222 

9S 

M 

N.  Y  Navy  Yard 

Locomotive  type 

„ 

5  3 

0.0 

116  4 

94 

" 

(l 

95 

tl 

M 

C( 

41 

tt 

it 

% 

it 

i« 

„ 

u 

44 

(t 

97 

" 

" 

M 

it 

tt 

t  « 

98 

" 

II 

H 

tt 

it 

99 

M 

tt 

., 

M 

tt 

it 

100 

M 

tl 

C( 

II 

•t 

•< 

101 

M 

" 

(( 

II 

tt 

tt 

10? 

cc 

M 

Return  fire  tube  

n 

10.8 

150 

103 

" 

» 

tt 

104 

" 

M 

(i 

tt 

tt 

tt 

105 

«t 

M 

II 

tt 

» 

I0f> 

" 

H 

tl 

tt 

Cl 

107 

M 

M 

M 

Gas  coke 

(t 

II 

108 

It 

If 

U 

Scotch  Cannel 

tt 

«: 

109 

M 

H 

M 

tt 

125 

110 

M 

" 

4i 

^ 

111 

tt 

Cl 

tt 

100 

m 

" 

it 

tt 

113 

M 

•• 

" 

tt 

" 

75 

114 

M 

M 

II 

tt 

tt 

115 

c 

U 

U 

tt 

8.6 

149 

116 

« 

tt 

i 

tt 

117 

1 

M 

I                                                      .... 

tt 

6  5 

148 

118 

« 

M 

' 

tt 

119 

« 

« 

1 

tt 

4  3 

147 

120 

• 

" 

1 

tt 

1711 

. 

M 

I. 

H 

10  8 

150 

122 

" 

" 

.         . 

M 

123 
124 

tt 



M 

tt              

44 

„ 

1?f> 

M 

II 

4, 

4i 

45  5 

ITlfi 

" 

M 

M 

tt              

It 

it 

127 

" 

" 

" 

(t              

(t 

tt 

128 

•  « 

U.  S.  S.Kansas  

Locomotive  type  .  .  . 

tt 

54 

1539 

129 

" 

tt             *     '  " 

tt 

ii 

130 

" 

« 

1C 

tt 

u 

it 

131 

M 

(i 

M 

tc              

it 

Cl 

132 

M 

U.S.  S.  Chippewa  

M 

89 

2919 

133 

M 

U.  S.  S.  James  Adger  

M 

tt 

99 

2060 

184 

" 

M 

" 

Cumberland!  !  '. 

it 

cc 

ON  COMBUSTION. 


27 


..  1  Steam  heating  sur- 
"85  1  face  in  sq.  ft. 

2 
1 

o> 
pi 

"•»i 
Id- 

0)   CC 

J 

6.9 

<u' 
a 

2 
o 

°£ 

*£ 
1* 

7.1 

Height  of  chim- 
ney. 

,52  j  Water  heating  sur- 
'  to  |  face  -r-  grate  area. 

,-i  Steam  heating  sur- 
"  ''0  face  -r-  grate  area. 

"So 
1 
•1- 

gg! 

C3  S 

II 

O 
1.1 

_^  1  Grate  area  -i-  chim- 
"  rb  1  ney  area. 

*§ 

»f! 

"rt  ft 

I 

.a  W> 

r3 

17.7 
16.6 
16.1 
14.4 

17.0 
15.1 
13.2 
15.3 
11.8 

9.5 
10.1 
8.9 
4.6 
11.5 

11.8 
10.9 
14.3 

15.9 
14.3 
14.4 

12.5 
20.5 
20.1 

3.6 
11.0 
16.6 
22.1 
27.8 

16.6 
16.6 

16.6 
13.7 
16.6 
11.0 
16.4 
7.5 

15.1 
20.7 
14.9 
27.4 
15.4 

i 

s 
1 

1 

17.4 

18.7 
18.8 
19.0 

19.9 
21.5 
21.4 
21.7 
16.4 

15.4 
11.8 
18.2 
25.0 
18.4 

19.5 
19.6 
21.5 

18.8 
18.1 
19.2 

23.9 
21.6 

22.8 

14.9 
14.7 
18.6 
17.7 
24.2 

8.6 
3.2 

22.1 
16.4 
20.0 
15.4 
24.9 
15.6 

19.6 
17.8 
22.9 
21.6 
?1  4 

EVAPOKA- 
T'N  FKOM 
&  AT  212°. 

Sd 

g§ 

rffi 

**Sfe 

A& 

8.9 
8.9 
9.1 
8.8 

8.7 
8.9 
8.5 
8.9 
9.1 

8.0 
10.3 
9.7 
12.1 
9.4 

7.6 
7.7 
7.2 

7.4 
7.4 
7.5 

7.0 
7.4 
8.9 

7.9 
7.6 
6.8 
6.7 
6.3 

7.6 
8.6 

6.3 
7.0 
7.0 
7.6 
6.7 
9.3 

7.2 
6.8 
7.1 
6.3 
7.6 

Si 

«« 

3^ 

10.7 
11.  0| 
11.3! 
10.9 

10.8 
11.3 
10.8 
11.3 
10.9 

9.4 
11.6 
11.  8l 
13.5 
11.1 

9.4 
9.5 
9.i 

9.1 
9.1 
9.2 

9.2 
9.5 
11.5 

9.3 
9.0 
8.3 
8.1 

7.8 

8.3 
8.8 

8.1 
8.4 
8.7 
8.9 
8.9 
11.0 

9.1 
8.3 
9.2 
8.1 

9  7 

ft.  in. 

50     ! 

" 

190 
65 
170 
70 
100 

u 

2.0 
it 

.c 

;• 

* 

" 

« 

« 

« 

8.5 
4.2 
4.4 
3.1 
6.0 

0  27 

12.6 
4.9 
6.3 

5.9 

7.9 

1.77 

63 
35 
52 
37 
45.9 

16.6 

21.3 
29.6 
25.2 
27.7 
21.9 

21.9 

tt 

1.6 
1.9 
3.8 
1.9 

1.8 

°»2 

13.8 
8.1 
10.0 
12.0 
9.4 

19.^4 

M 

10;9 

9.3 
6.9 
7.0 
6.3 
7.1 

8*;° 
(t 

15;0 

" 

" 

i, 

M 

o 
1  0 

(M 

30.7jia;9 

" 

14.5 
21.8 
43.6 

8.J 
6.5 

« 

" 

" 

M 

" 

M 

M 

0.64 

" 

tt 

11.6 

" 
" 

H 

(I 

H 

H 

0.49 
0.25 

M 

M 

» 

9.2 

U 

" 

6;9 
17.2 

u 

22.8 

" 

« 

M 

34.0 

M 

4.4 

14.3 
23.5 
52.8 
10.9 

15.0 
21.2 
43.4 

5.5 
6.6 
8.5 
10.3 

6.2 

10;0 

H 

t( 
M 

40 

36 
164 

0.74 
0.46 
0.20 
1.0 

0.72 

H 

.1 

H 

II 

(i 

27.6 

16.5 
16.6 
5.8 
16.5 

16.6 
16.6 
11.8 

17.0 
15.7 
16.1 
13.3 

8.3 
10.3 
9.5 

21.4 

19.3 
20.0 
22.4 
16.4 

20.3 
17.9 
27.1 

10.9 
16.6 
18.2 
18.7 

13.6 
11.1 
9.6 

6.2 

6.8 
6.9 
8.6 
7.0 

5.0 
5.2 
5.7 

8.5 
9.0 
8.8 
9.4 

10.6 
7.6 
8.7 

8.2 

8.6 
8.6 
11.1 
8.4 

6.3 
6.3 

7.8 

10.2 
10.8 
10.8 
11.6 

11  '.0 
8.7 
9.6 

;: 

4.2 

M 

11.51 

0.25 

9.9 
8.2 
9.6 
5.2 

14.2 
9.9 

8.7 

50 

28.5 

0.7 

12,6 
28  3 

'  48 
46 

32.9 
20;1 

0.4 
1.7 

5 

48 


7-2 


120 


Uncovered. 
Covered  with  felt. 


Air  holes  above  grate  0.4  sq.in. 
per  sq.  ft.  grate. 

Air  as  above. 
No  tubes  out. 
Chimney  on  back  connection. 


28 


STEAM  MAKING;  OR,  EOILER  PRACTICE. 


Number  for  Refer- 
ence. 

AUTHORITY. 

LOCATION. 

KIND  OF  BOILER. 

KIND  OF  FUEL. 

Grate  urea  in  square 
t'eet. 

H 

B 

oc 

gs 

p 

^•2 

'-  A) 

II 

135 

136 
137 
138 
139 
140 
141 
142 

143 

144 
145 

146 
147 
148 
149 

150 
151 

152 
153 
154 

155 
156 

157 

158 
159 

160 

161 
162 
163 

164 

165 
166 
167 

168 
169 
170 
171 
172 

173 
174 

175 
176 

177 

178 

179 

180 

181 
182 
183 

184 

185 

D.  K.  Clark  

Wlgan,  Eng         .         12  "Lannashirfi     TJit    mal 

31.5 
.t 

21 
31.5 

1C 

21 
10.3 

ti 
5.82 

19.2 
22 

18 
15.5 

42 

33 
22 

464 
767 

1314 
1617 

7f.7 

ier 

431 

719 

128] 
156S 

719 

156' 
508 

301 

503 

tt 
(t 
tt 
106 

it 
it 

749 

tt 

:;    :::;:; 

ii 

tt 

i 

it 

tt 

'                              4    .. 

M 

tt 

II 

«t 

,                              

tt 

tt                                                                                                               .4 

H 

tl                                                                                                                tt 



„ 

tl 

„ 

tt                                                                                                               It 

u 

M 

It                                                                                                               tt 

1, 

M 

K 

ti 

M 

tt                                                                                           tt 

.1 

M 

tt                                                                                            "t 

11 

It 

tt                                                                                           tl 

It 

1. 

"                          i                "                   



M 

l  Galloway  

tt 

II 

tt 

"           

H 

tt 

tt 

t( 

it 

tt 

M 

«, 

t. 

„ 

it 

tt 

ti 

|, 

H 

tt 

tt 

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M 

u 

tt 

II 

t< 

ti 

If 

„ 

14 

n 

(, 

It 

Return  fire  tube    

tt 

4. 

tc 

tt 

II 

tt 

M 

tt 

It 

it 

(i 

tt 

II 

tt 

tt 

tt 

M 

tt 

tt 

tl 

tl 

tt 

(t 

It 

M 

tt 

tt 

Newcastle  — 
Wesh  
Lancashire.... 
Best  Lancas're 
Lowest     ' 

Hartley  

M 

tt 

4t                       

11 

tt 

It 

tt 

tt 

It 

tt 

it 

U 

Newcastle  

Return  fire  tube 

tt 

„ 

tt 

(1 

ii 

tt 

n 

II 

tt 

u 

n 

u 

tt 

(t 

ii 

« 

tt 

It 

ti 

tt 

tt 

Newcastle  

tt 

M 

M 

tt 

it 

tt 

tl 

;; 

It 

M 

tl 

it 

" 

M 

Steam  heating  sur- 
face in  sq.  ft. 
Least  flue  area  in 
sq.  ft. 

Area  of  chimnev. 
Sq.  ft. 

Height  of  chim- 
ney. 

Water  heating  sur- 
face -r-  grate  area. 

Steam  heating  sur- 
face -=-  grate  area. 

1 

|| 
|| 

Grate  area  -r-  chim- 
ney area. 

Lbs.  coal  per  sq.  ft. 
grate  per  hour. 

Per  cent  refuse. 

EVAP( 
T'NP 
&AT 

I 

3EA- 
KOM 
212°. 

fj 

Duration  in  hours. 

ft.  in. 

164 

9.9 

21 

9t>.9 

15 

1.7 

10.0 

15.0 

9.5 

T8.6 
19.1 
20.1 
19.5 
17.6 
20.5- 
81.0 

20.8 
16.9 

22.7 
21.6 
23.0 
23.8 

6.4 

8.2 

10.3 
10.2 
9.6 
10.4 
10.6 
10.3 
10.3 

10.8 

11.5 
11.5 

10.9 
10.8 
10.6 
10.6 

11.6 
8.5 

10.2 
9.7 
9.9 

10.2 
11.8 

10.8 
10.7 
11.1 

11.9 

11.4 
11.8 

8.6 

11.0 
10.9 
10.3 
11.1 
11.3 
11.0 
11.0 

11.5 

12.3 
12.3 

11.6 
11.5 
11.3 
11.3 

12.4 
9.0 

10.9 
10.4 
10.6 

10.9 
12.7 

11.6 
11.4 
12.0 

12.9 

48 

t; 

•• 

M 

M 

« 

i4 

11 

« 

" 

M 

M 

;; 

« 

'« 

41.4 
51t't3 
36.5 

tt 

(t 

« 

- 

tt 

" 
77 
13.6 
22.8 

•• 

" 

tt 

18.3  !     " 
20.0  \ 
18.9 

18.4       " 

21.8       " 
22.7 
22.6 

20.9 

27.6 
24.0  i 

II 

it 

" 

II    !          M 

40.6 
50 
34.3 

; 

tl 

j 

" 

74.7 
50t 

» 

3.5 

5.7 

(i 

V 

y 

59.8 

1.4 

1.8 
1.8 

H 

27.9 
50  1 

" 

3.5 
3.5 

5.7 
5.J 

25.0 

24.0 

27.6 
27.5 
41.2 

28.8 
26.2 
27.6 
25.5 

;; 

12.2 

11.5 
11.9 
11.4 

11.9 
12.4 
11.5 
12.5 

» 

;; 

" 

» 

» 

M 

„ 

»« 

>i 

it 

ii 

5.7 

4.9 

37.5—7- 

5.0 

5.8 

31.4 

21.1 
19.0 

21.0 
17.2 

17.3 

it 
>i 

8.9 
11.1 

10.0 
12.5 

11.7 

« 

;; 

55.6     "  i     ** 

48.6     " 

it 
It 

« 

« 

*• 

59.6 
69 

25.5 

M 
„ 

tt 

27.0 

27.4 
37.4 

16.0 
17.6 
18.1 

20.4 
26.9 

" 

10.8 

11.4 
10.6 

9.6 
9.1 
9.0 

9.2 
10.3 

ti 

;; 

11 

32.3 
34 

M 

M 

REMARKS 


Without  side  flues. 


Without    side    flue,     with 
economizer. 


Without  ecoromizer. 


With  economizer. 
Without  side  flues. 


j  Without    side    flue,      with 
\     economizer. 


With  economizer. 
Average  15  trials. 


Natural  draft. 
Fan  draft. 


j  Including    heater : 
I     through  door. 


no    air 


Without  heater. 


30 


STEAM  MAKING;  OR,  BOILER  PRACTICE. 


Number  for  Refer- 
ence. 

AUTHORITY. 

LOCATION. 

KIND  OF  EOELEB. 

KIND   OF  FUEL. 

Grate  area  in  square 
feet. 

Water  heating  sur- 
face in  sq.  ft. 

186 
187 
188 

189 
190 
191 
192 
193 
194 
195 
196 

197 
198 
199 
200 
201 

202 
203 
204 
205 
206 
207 
208 

209 
210 

211 
212 
213 
214 
215 

216 
217 
218 
219 
220 
221 

222 
223 
22' 
225 
226 
227 
228 

229 
230 
231 

232 
233 
234 
235 

236 
237 

238 
239 
240 

241 
242 

D     K     Clark.                Npwnastlp                                        Rpf.iirn  firp  t.rihp 

Newcastle  

"          .  '.'.'.'. 
Welsh 

22 
\\ 

" 
tt 

<t 

18 
14 

10.5 
36 

30 
11 

749 

1069 

tt 
it 

tt 
tt 

485 

;; 
tt 

950 

t                                                                                           it 

1 

tt 

t 

tt 

tt 

I 

tt 

Newcastle  

tt 

I 

tt 

tl 

t 

tt 

t 

t          

' 

Welch 

tt 

I 

tt 

" 

t 

tt 

•t 

1 

tt 

tt 

I 

it 

II 

, 

u 

II 

4 

tt 

t 

tt 



1 

tt 

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tt 

tt 

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,, 

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n 

tt 

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" 

tt 

tt 

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tt 

M 

" 

" 

tt 

tt 

" 

it 

tt 

tt 

tt 

» 

t« 

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, 

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n 

Newcastle  
English 

t 

u. 

tt 

;     :.::::: 

Keyham  Yard 

tt 

tt 

" 

tt 

tt 

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tt 

tt 

t 

.1 

tt 

tt 

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tt 

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tt     

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tt 

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tt 

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I                                                                                                                       t< 

,t     

. 

M 

N.  Y.  Navy  Yard  

tt 

tt 

R.  H.Buel  

tt 

Anthracite  — 

14                                                                                                                       i4 

II 

"                  

It 

M 

tt 

tt 

tt 

1C 

tt 

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" 

" 

-ON  COMBUSTION. 


i 

5 

S 

0) 

| 

%i 
d  s-i 

Sg 

1 

| 

c  B 

EVAPOKA- 
T'N  FKOM 

g 

CQ 

%z 

%$ 
&a 

a  <o 
JJ 
^ 

I? 

1 

Height  of  ch 
ney. 

Water  heating  s 
face  -f-  grate  a 

Steam  heating  t 
face  -r-  grate  ar 

•1- 

II 

0 

li 

S  ct 

p 

Lbs.  coal  per  sq, 
grate  per  hour 

Per  cent,  refuse. 

&AT2 

C6  § 
h^ 

12°. 

*£ 

Duration  in  hoi 

REMARKS. 

ft.  in. 

5.7 

4.9 

34 

27.0 

10.0 

" 

4t 

" 

35.6 

9.5 

11 

" 

" 

31  6 

8.2 

" 

" 

« 

23.2 

10.1 

" 

" 

48.6 

22.1 

11.4 

" 

" 

23.0 

10.6 

" 

" 

' 

26.0 

11.2 

" 

" 

' 

26.0 

10.3 

" 

" 

' 

28  5 

10.6 

" 

" 

' 

29.5 

9.6 

" 

* 

17.3 

10.5 

" 

" 

" 

27.5 

9.9 

" 

" 

" 

23.4 

10.1 

'• 

" 

" 

23.4 

10.8 

'' 

" 

" 

24.0 

10.1 

" 

" 

16.3 

12.0 

" 

18.3 

12.4 

" 

" 

20.6 

12.6 

i        " 

" 

20.9 

11.4 

i        " 

" 

21.9 

11.6 

!    » 

" 

22.4 

12.9 

" 

9.2 

10.9 

t                16 

" 

V 

24.1 

11.1 

u 

59.6 

18.7 

11.1 

" 

24.9 

11.0 

35.3 

15.4 

10.4 

Common  doors. 

18.6 

9.2 

" 

15.4 

9.8 

" 

14.1 

10.1 

" 

15.7 

9.7 

i« 

16.7 

n'o 

" 

18.3 

9  4 

" 

16.2 

10.6 

" 

16.4 

10.6 

" 

16.4 

9.4 

" 

17.5 

11.2 

» 

14.9 

10.8 

Perforated  doors, 

" 

17.0 

9.6 

•' 

17.4 

10.5 

" 

16.6 

10.6 

" 

17.4 

10.4 

I 

it 

22.9 

9  3 

I 

" 

18.4 

10.8 

'  | 

47 

22.5 

11.3 

Common  doors. 

21.6 

11.1 

'' 

1 

22.8 

10.6 

it 

24.4 

11.4 

Perforated  doors, 

" 

22.3 

11.6 

4.6 

6-8  >  60.0 

26.4 

0.128 

19.4 

9.6 

" 

19.7 

9.4 

| 

(i 

19.5 

9.5 

| 

" 

18.8 

9  S 

4« 

13.1 

11.  £ 

" 

16.9 

12.  " 

1 

" 

7.8 

11.4 

31.7 

.153 

17.8 

10  F 

\ 

8.6 

12.21 

32 


STEAM  MAKING;  OR,  BOILER  PRACTICE. 


w 
w 

h 

<2 

li 

AUTHORITY. 

LOCATION. 

KIND  OF  BOILER. 

KIND  OF  FUEL. 

Grate  area  in  square 
feet. 

•M 

0 

t» 

%z 

•5  6" 

C8   05 

V 

a  ^ 

§g 

|" 

243 
244 
245 

246 
247 
248 
249 
250 

251 
252 
253 
254 
255 

256 
257 
258 
259 
260 

261 
262 
263 
264 
265 

266 
267 
268 
269 
270 

271 

i72 
273 

274 
275 

276 
277 
278 
279 
280 

281 
282 
283 
284 
285 

286 
287 
288 
289 
290 

291 
292 
293 
294 
295 

296 
297 
298 
299 

H  H  Buel 

N.  Y.  Nnvv  Yard 

Return  tire  tube. 

Anthracite  

ti 
tt 

24 

18 
tt 

13.5 
3.6 
ii 

ti 

28.8 
21.6 
29 
36 

22 
36 

36 

27 
36 

41 

950 

tt 

ti 

it 
ti 

ti  • 

n                                                    It  •" 

ti 

ii 

44 

it 

It 

14 

ti 

II 

H 

44 

It 

" 

44 

44 

44 

tl 

44 

tl 

,t                                       

II 

;;     ::::::::: 

tl 

4t                                       

44 

4t 

II 

It 

II 

It 

44 

II 

it 

::    ;;:: 

II 

II 

II 

It 

;;       .".'I"!" 

II 

II 



It 

41 

It                                                                                                                        II 

tl                                                                                                            14 

tl 

11                                                                                                            It 

il                                                                                                            tl 



II 

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It 

"                        _  _ 

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44 

4t 

;    '••• 

||                        

It 

41 

"                                    

41 

II 

4t 

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44 

44 

44 

.4 

It 

It 

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"                                    

It 

44 

,,                        

u                                    

44 

4; 

tt 

tl 

41 

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4t                                    

44                                    

44 

n                          

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44 

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II 

I, 

II 

44 

44 

44 

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41 

44 

It 

44 

II 

44 

tl 

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t|                        

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II 

t4                                    

44 

44                        

14 

tt 

44 

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11 

II 

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H 

tl 

44 

it 

It 

It 

ti 

" 

4' 

'» 

" 

ON  COMBUSTION. 


Steam  heating  sur- 
face in  sq.  ft. 
Least  flue  area  in 
sq.  ft, 

Area  of  chimney. 
Sq.  ft. 

Height  of  chim- 
ney. 

Water  heating  sur- 
face -i-  grate  area. 

Steam  heating  sur- 
face -i-  grate  area. 

49 

3) 

T- 

ii 

0 

Grate  area  -i-  chim- 
ney area. 

Lbs.  coal  per  sq.  ft. 
grate  per  hour. 

1  Per  cent  refuse. 

EVAP( 
T'NF 
&  AT 

¥ 

*fi 

3^ 

)RA- 
BOM 

212°. 

«s 
|§ 

«-fi 
g» 

Duration  in  hours. 

REMARKS. 

ft.  in. 

4.6      6.8 

60 

39.5 

.192 
.256 

.341 
.128 

« 

.16 
.213 
.159 

.128 

« 

1C 

.209 
.106 

.102 
.095 
.114 
.1 
.128 

(i 

.114 

.128 

.128 

.148 
.108 
.067 

.087 
.111 
.099 

.085 
.071 
.057 
.043 
.028 

.014 
.083 

17.7 
8.7 
19.1 

8.4 
10.0 
8.1 
7.1 
17.9 

3.7 
16.7 
12.1 
17.6 
15.7 

15.2 
18.5 
14.6 
18.4 
20.3 

18.6 
21.4 
18.6 
21.9 
18.6 

18.5 
18.6 
16.6 
16.7 
17.4 

18.6 
17.1 
18-7 
22.4 
21.7 

21.7 
21.6 
22.1 
15.2 
14  9 

15.2 
21.7 
19.0 
18.3 

18.7 

7.9 
13.7 
15.4 
15  5 
14.0 

13.4 
11.6 
11.2 

8.6 
5.8 

2.4 
14.1 
15.2 
14.4 

11.5 
11.6 
11.5 

12.3 
11.3 
12.3 
12.7 
10.0 

13.1 

10.0 
11.0 
10.4 
10.6 

11.5 
11.6 
11.6 
10.4 
7.5 

9.4 
7.4 
9  7 
11.2 
10.8 

10.8 
10.9 
11.4 
11.2 
11.3 

10.7 
10.5 
10.6 
10.0 
9.9 

9.2 
11.1 
11.4 
12'0 
12.7 

12.2 
11.8 
12.9 
11.2 
5.9 

8.2 
6-9 
11.5 
11-4 
11.6 

11.7 
12.8 
11.8 
12-3 
12.4 

13.6 
11.7 
11.5 
11.7 

" 

" 

" 

52.8 

M 

, 

it 

70.4 
26.4 

u 

« 

"                  tC 

l(   1       (( 

u 
M 

33 
44 
32.8 
26.4 

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M 

«i 

»     !! 

1* 

43.2 
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M 

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1! 

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26.4 

35.2 
26.4 
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26.4 

M 

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21.1 

19.9 
17.7 
15.5 
13.4 
11.2 

9.1 
26.4 

"                *" 

"                "* 

34 


STEAM  MAKING;  OR,  BOILER  PRACTICE. 


Number  for  Eefer-  1 
ence. 

AUTHORITY. 

LOCATION. 

KIND  OF  BOILER. 

KIND   OF  FUEL. 

Grate  area  in  square 
feet. 

Water  heating  sur- 
face in  sq.  ft. 

300 

301 
302 
303 
304 
305 

306 
307 
3U8 
309 
310 
311 

312 
313 
314 
315 
316 

317 
318 
319 
320 
321 

322 
323 
324 
325 
326 

327 
328 
329 
330 
331 

332 
333 
334 
335 
336 

337 
338 
339 
340 
341 

342 
343 
344 
345 
346 

347 
348 
349 
350 
351 

352 
353 
354 
355 
366 

B.  H.  Buel  

N.  Y.  Navy  Yard  

Return  fire  tube  

Anthracite  — 

36 

31;2 

36 

44 

39 

41 

36 
39 
30 

24 

18 
13.5 

44 

39 

36 

39 
36 
31.2 
23.4 
31.4 

36 

44 

39 
36 

39 

36 

39 

23.8 

39 

950 

44 

1265 

44 

4 
4 

44 
44 

(4 

H 

44 

44 
44 

44 

H 

ii 

« 

H 

« 

44 

II 

M 

" 

44 

« 



II 

« 

M 

Return  water  tube  

" 

44 

" 

" 

(4 

,4                        

44 

ii 

(4 
4( 

44 

M 

M 

H 

||                          

U 

" 

II 

H 

44 

M 

„                    

M 

ti 

M 

><                                .  .  .  . 

M 

II 

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" 

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II 

" 

(4 

«' 

„                          

H 

II 

44                                           •      •  .  . 

;;    •••• 

II 

« 

u 

M 

«4 

44 

II 

M 

M 



'« 

44 

44 

II 

u 

" 

« 

44 

II 

M 

II 

44                    '  "  "  ' 

" 

" 

44 

11 

4« 



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II 

M 

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« 

44 

M 

44 

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" 

44 

" 

44 

1 

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Ci 

44 

II 

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11 

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il                                   ... 

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44 

44 

M 

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" 

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M 

44 

4. 

II 

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44 

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lt 

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»    :::: 

1, 

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tt                         

44 

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44 

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tt 

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ON  COMBUSTION. 


35 


heating  sur-  \ 
n  sq.  ft.  1 

a 

i 

i  . 

Df  chimney. 

IT.  • 

:ght  of  chim- 
ey. 

heating  sur- 
T-  grate  area. 

si& 

+ 

^  C8      TO  re 

o 

•1'  . 

f& 

it.  refuse. 

EVAPO 
T'NF] 
&ATS 

RA- 
IOM 

12°. 

2 

o 

d 
| 

REMARKS. 

g'<D 

I1 

*  CC 
A 

g 

5  a 
W 

>H    Q) 

I1 

|| 

1111 

0       0 

§1 
.§& 

i 
1 

ji 

I* 

0 

Q 

ft.  in. 

4.6 

6.8 

60 

40.4 

.142 

11.4 

11.6 

" 

44 

" 

14 

18.3 

1.0 

'  l 

44 

44 

44 

44 

14.5 

11  5 

" 

" 

N 

11 

44 

5.0 

12.6 

" 

44 

14 

41 

1C 

3.4 

11.2 

t4 

«i 

" 

26.4 

-100 

6.8 

12  0 

" 

u 

44 

44 

" 

10.3 

11.8 

5.54 

6.78 

" 

32.4 

.142 

12-8 

10.8 

" 

4* 

" 

" 

" 

12.3 

12  1 

" 

" 

" 

44 

12.7 

11.9 

6 

12  5 

11  8 

" 

" 

" 

11.8 

,\' 

12.0 

" 

" 

44 

35.1 

.154 

11.5 

12.3 

" 

" 

44 

32.4 

.142 

7.3 

3.3 

" 

" 

ii 

42.2 

.185 

11.6 

13.0 

lt 

8.6 

13.3 

" 

" 

" 

52.7 

.231 

12.2 

13  5 

" 

Cl 

44 

» 

44 

8.6 

12.7 

" 

" 

14 

70.3 

.308 

12.7 

13.3 

44 

" 

1C 

44 

8.3 

13.4 

" 

" 

'' 

93.7 

.411 

12.0 

12.8 

ii 

1*1          (I 

" 

8.0 

13.8 

" 

44          II 

32.4 

.142 

6.5 

13.5 

I.      |           1C 

" 

fct 

12-2 

10..  5 

'* 

3  4 

13.7 

" 

1C                It 

35.1 

.154 

10-3 

12.7 

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II     II 

11.9 

12.2 

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II 

ii 

32.4 

.142 

16  0 

11.0 

" 

II 

" 

35.1 

.154 

15.1 

11.0 

i 

II                  IS 

40.5 

.178 

9.6 

13.0 

1 

11     :          1C 

54.1 

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12.2 

13.2 

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1C 

40.3 

.177 

10.4 

13.1 

' 

" 

" 

35.1 

.154 

18.4 

10.6 

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12.5 

12.8 

w 

" 

14-7 

13.0 

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4t 

44 

13.8 

12  9 

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" 

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14.7 

12.9 

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44 

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32.4 

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11.8 

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17.4 

11.6 

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32.4 

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12.1 

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ii 

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16.4 

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11.5 

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15.4 

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44 

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17.0 

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15.3 

11.0 

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11 

32-4 

.10  | 

9-5 

13.3 

36 


STEAM  MAKING;  OR,  BOILER  PRACTICE. 


Number  for  Refer- 
ence. 

AUTHORITY. 

LOCATION. 

• 

KIND  OF  BOILER. 

KIND  OF  FUEL. 

Grate  area  in  square 

feet. 

Water  heating  sur- 
face in  sq.  ft. 

357 

R.  H.  Buel  

N.  Y.  Navy  Yard 

Return  water  tube  

Anthracite 

39 

1265 

:-i58 

359 

" 

it 

'i 

44 

36 

u 

360 

H 

M 

it 

4t 

39 

11 

361 

H 

II 

M 

tt 

ii 

362 

1. 

,4 

tl 

41 

41 

11 

363 

11 

II 

II 

tt 

it 

u 

364 

" 

II 

" 

44 

ti 

u 

365 

" 

it 

" 

" 

36 

ii 

366 

M 

M 

'1 

II 

39 

it 

367 

4. 

,t 

14 

tt 

,t 

368 

" 

It 

41 

II 

tt 

tt 

369 

to 

u 

It 

II 

ti 

ti 

370 

I' 

It 

11 

11 

41 

it 

371 

«' 

M 

'I 

41 

II 

u 

37*> 

H 

t< 

tt 

tt 

36 

,i 

373 

• 

U 

44 

II 

39 

ti 

374 

1 

II 

" 

" 

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375 

i 

M 

H 

it 

tt 

ti 

376 

11 

" 

14 

it 

» 

377 

' 

„ 

II 

tt 

M 

ti 

378 

« 

It 

41 

II 

It 

(i 

374 

' 

K 

It 

It 

tt 

tt 

380 

1 

1' 

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" 

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381 

* 

It 

II 

II 

tt 

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38? 

It 

II 

14 

It 

ti 

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tt 

tt 

11 

tt 

384 

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tt 

18 

it 

485 

II 

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386 

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41 

18 

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387 

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44 

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389 

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41 

391 

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t 

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392 

H 

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393 

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tl 

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394 

II 

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tt 

14 

i 

41 

395 

n                 

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t 

11 

396 

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it 

II 

397 

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tt 

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398 

1.                    

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11 

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399 

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400 

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401 

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C.  Linde' 

Augsburg 

Three  French  boilers  eacl 

\ 

21 

644 

;     with  two  heaters  
iTwo  tubular  return  .  .  .  .  j 

•-J 

22 

20. 

481 
5      644 

1 

24 

iau-2 

ON  COMBUSTION. 


37 


1  Steam  heating  sur-  ( 
face  in  sq.  ft. 

a 

a 
<u 

a 
| 

if 

>-. 

<X> 

a 
j 

0 

°£ 

«8  6* 

«£ 

<! 

Height  of  chim- 
ney. 

Water  heating  sur- 
face -j-  grate  area. 

Steam  heating  sur- 
face -r-  grate  area. 

Grate  area  -j-  least 
flue  area. 

Grate  area  -r-  chim- 
ney area. 

Lbs.  coal  per  sq.  ft. 
grate  per  hour. 

Per  cent  refuse. 

EVAPC 
T'NF 
&AT 

¥i 

»•£ 
^ 

1  Lbs.  water  1 
I  ^  Ib.  com.  1  .og^T 

Duration  in  hours. 

REMARKS. 

ft.  in. 

5.54 

6.78                 32.4 

.10 

i     11.5 

13.1 

•' 

" 

" 

6.4 

13.4 

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" 

35.1 

.154 

17.7 

11.2 

" 

44 

32.4 

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11.1 

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it  . 

15.4 

11.7 

H 

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16.8 

11.8 

44 

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20.1 

9.8 

44 

11 

35.1 

154 

21.6 

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32.4 

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26.9 

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14.4 

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19.5 

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32.4 

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14.9 

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31.2 

tt 

tt          ,           it 

10.1 

•4 

44 

13,2 

j      ' 

" 

11 

tl    • 

" 

11.7 

ti 

" 

12.5 

< 

•• 

it 

.100 

tt 

44 

17.4 

44 

4- 

12,2 

4 

" 

29.1 

.142 

it                     it 

10.0 

" 

44 

12  9 

44 

M 

il                     it 

12.  € 

44 

4< 

12.6 

" 

" 
" 

27.0 

" 

it                     It 

10.3 

ti  j      it 

12.7 

" 

• 

13.1 

12,0 

44 

" 

24.9 

" 

"         "        10.1 

tt 

12.5 

44 

** 

*t 

44 

14  6 

44 

44 

11.81 

M 

it 

22.8 

" 

" 

10.3 

" 

" 

12,1 

it 

4i 

ti 

44 

13.9 

44 

44 

11,6 

" 

ti 

20.7 

" 

" 

"        10.4 

44 

" 

12,2 

il 

" 

tc 

it 

tt 

"        15.9        " 

44 

11.2 

44 

" 

18.8 

»« 

44 

10.1   1 

" 

11,6 

li 

M 

44 

44 

16.3 

" 

*.* 

10.7 

44 

" 

16.5     " 

44 

*• 

10.1 

44 

" 

11,4 

i    n 

ti 

45 

33 


STEAM  MAKING;   OK,  BOILER  PRACTICE. 


Number  for  Refer- 
ence. 

AUTHORITY. 

LOCATION. 

KIND  OF  EOILEB. 

KIND  OF  FUEL. 

Grate  area  in  square 
feet. 

Water  heating  sur- 
face in  sq.  ft. 

411 
412 

413 
414 
415 

416 
417 

418 
419 
420 
421 

422 
423 
424 

425 
426 

427 

4^8 
429 

430 
431 
432 

433 
434 

435 
436 
437 
438 
439 
440 
441 
442 

443 
444 
445 

446 
447 

448 

449 
450 
451 
452 
453 
454 
455 

456 
457 
458 
459 
460 
461 
462 

C  Linde' 

One  Lancashire  with  two 
cylinder  heaters 

Anthracite  

21 
24.5 

134 

99 

57 

57 
57 

55.2 
20.5 

27 
39  5 

36-6 

16 
27.5 

" 

158 
139 

64.5 

81.2 
64 

52.5 
30.2 

10.5 
15 

1302 
1100 

5473 

1573 

1689 
1805 

6125 

1017.5 

607  6 
Ci 

593 

1507 

698.5 

t» 

it 

1C 

6659 
6232 

3030 

3820 
3126 

2135 

644 

it 
tt 

Return  fire  tube  

u 

n 

Saarbruck  
Anthracite  
tt 

Ronchamp  

Saarbruck  
Ronchamp  

Saarbruck  
Ronchamp  

Saarbruck  
Anthracite  

Scotch... 

C.  E   Emery  

U,  S,  S.  Rush  
U    S    S    Dexter 

M 

U.  S   S,  Dallas  

M 

,t 

U,  S.  S.4Gallatin  

NorthRiver  

tt 

ti 

Mulhouse  

Lancashire  

ti 

If 

11 

11 

M 

M 

it 

H 

tt 

Fairbairn 

M 

M 

tt 

M 

»t 

n 

M 

French 

tt 

M 

II 

t: 

u 

B.  H.  Thurston  .  .  . 
L.  E.  Fletcher  

New  York    . 

t, 

Sinclair  

11 

Welch  ..  .. 

<t 
"            

u 
H 

H 

C  Linde' 

i(                                                                                                          1C 

Scotch 

tt 

Lancashire 

11 

1C 

London,  at  South  Metro- 
politan Gas  Works. 

(i 
Pf  ersee  near  Augsburg 
Oak  Mill 

it 

Gas  Coke  

11 

Welch  Coal.... 
Breeze  

ti 

11 

Welch(Coal.... 

1C 

Eight  French 

Saarbruck  
Bituminous..  .  . 

M.  Longridge  

N.  McDougall  

E.A.  Cowper  
M.  Longridge  

it 

Two  Lancashire  

"                              .       1                             

it 

Three  Lancashire 

11 

Two  Lancashire 

1C 

tt 

M 

Three  Cornish    

Blackburn 

11 

M 

,             

Pimlico  forW.  W.  at  Kim- 
berly 

One  Composite 

it 

lt             

tt 

« 

M 

ON  COMBUSTION. 


39 


3 

.2 

i 

a 

rj    8 

Sg 

ti 

i 

S 

e 

EVAPORA- 
T'N  FROM 

g 

Steam  heating  s 
face  in  sq.  ft. 

8 

as 

i, 
i* 

3" 

-= 
u 

«« 

w 

<i 

Height  of  ch 
ney. 

Water  heating  s 
face  -i-  grate  a 

QQ  i^ 

S3  aj 

•i- 
5  a 

85 

0 

Grate  area  -f-  ch 
ney  area. 

Lbs.  coal  per  sq. 
ijjrate  per  hour 

Per  cent,  refuse. 

&  AT  212°. 

Duration  in  hoi 

REMARKS. 

1  Steam  heati 
1  face  -4-  grat< 

h 

-2^3 

El 

a:fi 

^ 

3s 

|8 
.•fi 

3» 

ft.  in. 

3.9 

26 

120 

40 

4.0 

5.3 

" 

55 

7.6 

8.1 

7.7 

27.6 

7.4 

11.4 

21.1 

8.6 

10.8 

" 

27.6 

" 

12.0 

20.3 

8.7 

10.9 

7.8 

29.6 

7.3 

13.3 

20.5 

8.7 

11.0 

1051  702 

32.6 

2,0 

7.7 

16.2 

21.6 

8.2 

10,3 

'" 

" 

15.3 

St 

10.6 

n 

29.8 

18.5 

13.4 

'8.9 

10.3 

" 

10.1 

14.6 

9'.  3 

10.9 

" 

u 

19.0 

14.4 

7.8 

8.7 

" 

11 

16.1 

9.7 

9.0 

10.6 

u 

49.5 

18.0 

13.8 

9.6 

11.4 

" 

•« 

10.4 

13.4 

9.0 

10.4 

" 

" 

16.1 

10.5 

8.3 

9.2 

" 

30.3 

20.1 

14.5 

8.6 

10.0 

" 

" 

11.1 

13.6 

9.6 

10.4 

u 

" 

" 

16.9 

9.1 

7.9 

8.7 

294 

1.9 

4.4 

60 

22 

10.9 

14.1 

6.2 

comb. 

60 

« 

10.7 

" 

.  D 

coal. 

10.3 

38.1 

13.2 

10.4 

" 

10.7 

12.2 

11 

16.6 

8.3 

29 

23.2 

6.6 

" 

22.8 

6.5 

42.5 

8.4 

7.5 

" 

81 

11.4 

24.7 

4  S 

7.4 

•• 

4.1 

9.5 

" 

5.3 

8.8 

•   " 

6,4 

8.0 

46 

161 

42 

4.6 

44.4 

4  7 

47 

16  4 

9.C 

11.6 

15.6 

10.0 

12.0 

15.6 

10.8 

12.7 

47 

22.4 

11.0 

7.4 

8.3 

49 

19.8 

8.2 

9.8 

11,0 

" 

8.3 

71 

19.6 

11 

10.2 

11.4 

20.0 

10 

10.4 

11.5 

I 

20  0        9 

10.4 

11  5 

19.0 

10.4 

19.3 

10 

9.6 

11.1 

20.8 

8 

9.9 

10.8 

22.6 

9 

9.5 

10  .7 

11.3 

11.4 

10.5 

8.5 

10.8 

M 

5.7 

10.8 

«« 

4.2 

8.1 

43 

8.0 

11.2 

6.7 

11.5 

1         '       5.4 

11.5 

40 


STEAM  MAKING;  OR,  UOILER  PRACTICE. 


Number  for  Refer-  j 
ence. 

AUTHOBITY. 

LOCATION. 

KIND  OF  BOILEK. 

KIND  OF  FUEL. 

Grate  area  in  square  1 
feet. 

M 
P 
OS 

.3* 

'3  c? 

8! 

"2! 

II 

** 

463 

464 

465 
466 
467 

468 

469 
470 

471 

472 
473 

474 

475 
476 
477 

478 
479 

480 
481 
482 
483 

484 

485 
486 
487 
488 
489 

490 
491 

492 
493 
494 
495 
496 

497 
498 
499 

500 
501 
502 
503 

504 
505 
506 

507 

M.  Longridge   .  .  . 
Report  Committee. 

Pimlico  f  orAV.W.atKim'ly  . 
Dusseldorf  

One  composite 

Bituminous.  . 
Essen  coal  

Anthracite  .... 
Pittsburgh  

Cumberland... 

Anthracite  
Pittsburgh  .... 

15 

22 
ii 

33.4 

19.4 
19.7 

36.6 

15.8 
32.3 

13.7 

34.8 
15.8 
34.8 

12.6 
15.7 
45 

19 

42.7 
28.75 

38 

14.7 
34.3 

26.7 
23.1 

20.2 
22.5 
27.5 
32 

14.3 
14.1 

51 

644 

1520 

869 
1194 

1068 

1034 
724 

494 

2143 
389 
2142 

1942 
996 
329 

1083 

1977 
1020 

818 

1122 

817 
676 
1100 
818 

377 
1224 

1C 

ii 

" 

Lancashire,  with  tubu-  I 

tl 

Heine  water  tube. 

t< 

„ 

Cornish,  with  ret'n  tubes. 
Lancashire,  with  Gallo-  ( 

ii 

H 

„ 

i« 

Cornish  . 

« 

(t 

Steinmuller's  water  tube.. 
Neuman's,    with    water  / 

t, 

H 

M 

1C 

Lancashire,  with  Gallo-  1 
way  tubes,  and  tubu-  > 
lar  boiler  also.          .  .  .  ) 

„ 

M 



„ 

Lancashire,  with  Gallo-  J 
way  tubes,  and  tubu-  >- 
lar  above  ) 

M 

BUttner's  water  tube  
Watther's  water  tube  
2  exL  fired  ret.  6"  tube  — 

2  ext  fired  ret.  flue  ........ 

„ 

„ 

J  W  Hill 

Eva-isville  W  W     

" 

Cincinnati  W.  W  

>< 

li 

Holly  at  Buffalo,  N.  Y  
LawrenceW.  W  

2  North  River 

R  H  Buel 

Locomotive 

Report  Committee 

n 

u 

M 

Brooklyn  W.  W  

Rpt.nrn  rlrnn  flnp... 

|| 

Chicago  N  W  W    (Marine 

C*  Hermzvny 

Cincinnati  W  W           ....  Fina  *»•*+.  firpH. 

Flue  int.  fired  

I. 

Flue  ext.  fired  

M 

II 

ii 

i 

ii 

t 

M 

i       *  " 

Flue  int.  fired  •            .... 

n 

Anthracite  
H 

Pittsburgh!!!! 
Anthracite  .... 

Soft  ..!!!! 

Coking  
Illinois.... 

Hartford  W.  W  

« 

1C 

M 

«> 

Jersey  City  W.  W 

it 

u 

Louisville  W  W 

Return  drop  flue  
Return  tube  ext.  fired  

Return  flue  ext.  fired  

., 

M 

Lowell  W  W 

M 

Lynn  W.  W.                 

Johnson. 

Washington  W.  W    

" 

(C 

P.  W.  Schaumleffel 

St.  Louis  Lead  &  Oil  Co.. 

ON  COMBUSTION. 


41 


B     * 

i 

i 

Bg 

Bg 

49 

i 

1         *   • 

EVAPOKA- 
T'N  FKOM 

t 

|  Steam  heating  s 
face  in  sq.  ft. 

1 
1 

R 

I 
1 

Height  of  ch 
ney. 

1 
|l 

I  Steam  heating  i 
1  face  -i-  grate  a 

if 
II 

0 

Grate  area  -r-  ch 
ney  area. 

Lbs.  coal  per  sq 
grate  per  hour 

Per  cent  refuse. 

&  AT 

I 

212°. 

Id 

g8 

Duration  in  hou 

KEMABKS. 

ft.  in. 

4.0 

11.0 

2.7 

8.3 

9.2 

8.0 

10.8 

3.6 

11.2 

6.8 

11.2 

5.6 

43 

11.2 

10.9 

11.6 

5.3 

45 

18.8 

9.0 

10.8 

2.3 

50 

19.7 

11.0    12.0 

4.7 

29 

i     11.4 

10.0 

11.1 

4.4 

53 

;     20.4 

11.5 

12.2 

4.5 

22 

13.8 

8.8 

70,6 

^  — 

4.0 

36 

14.5 

8.7    10.6 

I 

5.3 

24 

14.6 

11.1    12.0 

4.2 

65 

19.5 

8.5      9.3 

5.3 

|     54 

15.6 

11.0 

12.2 

6.4 

74 

„.« 

10.5 

11.4 

3.4 

41 

17.5 

8.8 

9.9 

4.7 

i  2.70 

9.6 

8.0 

18.6 

8.4 

10.3 

!    " 

8.2 

11.5 

8.2 

9.3 

2.5 

56.9 

7.6 

20.4       3 

10.6 

10.9 

21.0 

10.0 

10.3 

5.8 

76 

46.1 

.189 

6.45  6.39 

13.6 

14.5 

120 

35.5 

.117 

8.38 

6.H 

11.5 

12.2 

7.07 

| 

9.22 

r  9.3 

21.5 

11.1 

13.1 

11.1 

10.2 

8.5 

20.4 

8.5 

1 

12.3 

8.4 

16.1 

8.5 

12.3 

8.3 

22.8 

8.8 

9.5 

48.5 

6.9 

12.4 

5.6 

11.5 



12.5 

40.4 

4.y 

11.5 

Mean  of  4. 

30 

10.1 

40 

9.9 

25.6 

13.9 

11.0 

26.8 
27.0 

6.6 
7.0 
7.4 

9.6 
9.7 
8.5 

7  samples. 
11  samples. 
10  samples. 

24 

13.3 

5.44 

1  week. 

42 


STEAM  MAKING;  OR,  BOILER  PRACTICE. 


Number  for  Refer- 
ence. 

AUTHORITY. 

LOCATION. 

KIND  OF  BOILER. 

KIND  OF  FUEL. 

Grate  area  in  square 
feet. 

Water  heating  sur- 
face in  sq.  ft. 

508 
509 
510 
511 
512 

513 
514 
515 

516 

517 
518 
519 
520 
521 
522 
523 

524 

525 
526 
527 
528 
529 
530 
531 

532 
533 
534 

P.  W.  Schaumleffel 

M 

C  A  Smith  .    .  . 

St.  Louis  Lead  &  Oil  Co.  . 

St.  Louis,  W'n  University 
S  S  Leila 

Return  flue  ext  .  ^fired  

n                    u 
Return  tube 

Illinois  

51 

" 

24 

48 

26 
U 

15.3 
8.3 

20.3 

36 

57 
35 

1224 

768 
1536 

485 

300 

272 

330 

932 

21515 

872 

M 

(( 

B.  F-  Isherwood  I 
and^Com'n.  ...    J 

Herreshof  coil. 

Anthracite  

Cumberland.  .  . 
Illinois  

n 

" 

M 

H 

H 

M 

H 

11                                                                                              (t 

((                                                                                              11 

"                                                                                              " 

C.  H.  Loring  and  1 
Commission...  f 

C.  A.tSmith  

S  S.  Anthracite.                  !  Per  kins. 

St.  Louis  
"                  

Heine  



u 

" 

" 

Herreshof. 

Anthracite  — 
Mt.  Olive  

F.  H.  Pond  

Edwardsville.  . 

Fluet  return  ext.^fired  

Return  tubular  ext.  fired. 
Return  flue  ext.  fired  

*• 

(C 

Edwardsville.  . 

J.W.Hill  



Saratoga 

Newnort.  TCv 

"       ;           " 

ON  COMBUSTION. 


43 


i 

a 

6 

jj 

i§ 

*$ 

1 

Jj 

s  B 

EVAPORA- 
T'N  FROM 

| 

GO 

t£« 

8 

fl 

rC 

02  5 
bt  n 

MiS 

J 

2 

0 

i's 

£ 

&  AT  212°. 

0 

B1*-1 

C$ 

2 

5M 

S-g     S3  0) 

•1- 

.1. 

S-'  .§ 

Q 

«     • 

O 

•3  f8 

1 

9- 

*rt1 

| 

d 

~  £ 

|I 

00 

Is* 

? 

i* 

'S  fl 
M 

Water  heal 
face  -7-  gi 

II 
ll 

II 

0 

Grate  area 
ney  area 

Lbs.  coal  p 
grate  per 

Per  cent,  n 

|1 

ij 

Duration  i 

REMARKS. 

ft.  in. 

24 

6.30 

1  week. 

11 

26 

6.54 

72  hours 

" 

5.70 

2  weeks. 

" 

6.5 

2  weeks. 

" 

7.1 

3  weeks. 

3.14 

6.28 

12.25 

100 

32 

7.G 

2.0 
4.0 

38 
24 

12.5 

6.9 
7.1 

8.  61  week. 
9.  3i  week. 

Coal  has  heating  power  .80  of 
carbon. 

" 

" 

7.9 

9.9 

24  hours 

44 

10.0 

3.14 

27 

18.7 

1.7 

3.9 

8.26 

12.8 

15 

8.2 

9.7 

11.8 

18 

8.1 

9.9 

11.3 

16 

8.2 

9.8 

8.3 

20 

9.1 

11.5 

7.9 

21 

8.4 

10.6 

5.0 

20 

8.3 

10.4 

•~'~, 

4.9 

22 

8.6 

10.9 

8.1 

13 

9.1 

11.2 

326 

3.7 

29.8 

30 

4.3 

12.0 

17.6 

9.3 

11.3 

1.8 

56 

32.7 

4.5 

22.5 

14 

6.0 

6.9 

32 

10 

5.6 

6.2 

40 

8 

5.8 

6.3 

125 

16.2 

10.3 

16 

7.3 

8.8 

16.6 

12.8 

5.9 

6.8 

26 

17.9 

11.5 

6.0 

6.7 

14.8 

21.5 

7.2 

8.4 

31.9 

5.8 

3.2 

11.3 

11.6 

5.6 

11.1 

€0 

24.9 

6.26 

15.3 

9.8 

8.5 

9.4 

Bearing's  setting. 

25.9 

4.4 

6.2 

6.5 

Common. 

44 


STEAM  MAKING;    OR  BOILER  PXACTK'E. 


LOCOMOTIVE  BOILERS. 


Number  for  Refer- 
ence. 

NAME. 

Area  of  grate.  Sq.  ft. 

Area  of  heating  sur- 
face. Sq.  ft. 

Heating  surface  -f- 
grate  surface. 

Coke  per  Rq.  ft.  of 
grate  per  hr.  in  Its. 

"S.S 

00  *-" 

p 

Pounds  water  evap- 
orated perlb.  fuel 
from  and  at  212° 

AUTHORITY. 

1 

2 

3 

4 
5 

6 

7 
8 
9 
10 

11 
12 
13 

14 

15 

16 
17 
18 
19 
20 

21 
22 
23 

24 

25 

26 

27 
28 
29 
30 

31 
32 
33 
34 

35 

36 
37 

38 

39 
40 

41 

Earliest  Engs. 
Killing  worth... 

Rocket 

7.0 
10.9 

6 
6 
9.2 

7.76 
6.5 

8.44 

8.34 
9.2 
9.2 

13.4 
13.6 

11.4 
12.5 
13.6 
11.7 
18.44 

13.67 
21 
21 

23.62 

9.6 

9.6 
19.56 
10.5 
19 
22 

14.7 
26.25 
12.25 
12.25 

14.7 

10.5 
10.5 

12.4 

16  ^ 

41 
124 

138 
326 
275 

359 

348 

412 

418 
461 
387 

699 
699 

467 
608 
699 
822 
1363 

1067 
1938 
1938 

1866 

903 

828 
1056 
782 
1449 
1263 

1158 
963 
706 
706 

1158 

623 
623 

985 
871 

6 
11.4 

23 
55 
30 

46 
53.5 

35 

49 
50 
42 

52 
51.4 

41. 
48.6 
51.4 
70.0 
74.0 

78 
92 
92 

79 

94 

86 
100 
74.5 
76.26 
57.41 

78.8 
36.7 
57.6 
57.6 

78.8 

59.3 
59.3 

79 
54.^4 

coal 
44 
57 
coke 
35.5 
54 
60 

92 
90 

1  100 

[-130 
i    92 

125 
111 
112 

138 
105 

97 
76 
69 
91 
69 

84 
82 
90 

75 

132 

105 
157 
90 
56  5 
50.7 

coal 
62.25 
38.86 
61.22 
44.49 
coke 
51.71 

55.91 
66.19 

87 
coal 
35 
57 

49 

2.3 
4 

3 
5.7 
5.14 

8.22 
9.8 
10 
13.03 
11.0 

11.3 
9.24 
8.15 

15 
15 

10.7 
8.8 
8.0 
10.8 
8.4 

11.2 
11 
11 

8.6 

17 

15 
22.1 
11.1 
6.2 
6.6 

12.26 

0.18 
9.65 

7.77 

4.02 
5.32 

6.27 
7.86 
6.35 

6.53 

8.04 
7.42 
7.38 
8.87 

6.65 
6.15 
4.93 

8.33 
10.70 

8.21 
8.61 
8.67 
8.85 
9.09 

9.90 
9.95 
9.17 

8.60 

10.52 

10.7 
10.41 
9.29 
8.23 
9.28 

10.15 
10.60 
10.13 
11.91 

9.77 

11.68 
10.96 

10.59 

11.02 
10.57 

9.90 

D.  K.  Clark. 
k* 

Phoenix    .. 

Atlas  

Star  

Average  of  4.  .  . 
isoho  

Hecla  
Burv'o 

G.  W.  R. 
Ixion  

Hercules  

Etna  &  1  
Giraffe 

Mentor  &  1  
Royal  Star  
Pyracmon  Cl  .  . 

Aiax  

Great    Britain 
Great     Britain 
class 

Courier  class... 

L.  &  N.  W.  R. 
A 

Hercules  

Sphinx 

No.  291  

No.  300.    . 

8.  E.  R. 
No.  142  

No  118 

No.  58 

No.  58  
No  142 

No.  105  

No  9 

L.  AS.  W.R. 

Snake  

Canute  

» 

ON  COMBUSTION. 


45 


Number  for  Refer-  I 
ence. 

NAME. 

Area  of  grate.  Sq.ft. 

Area  of  heating  sur- 
face. Sq.  ft. 

Heating  surface  -f- 
grate  surface. 

Coke  per  sq.  ft.  of 
grate  per  hr.  in  fibs. 

Water  per  sq.  ft.  of 
grate  per  hour  in 
cubic  ft. 

Pounds  water  evap- 
orated per  ft.  fuel 
from  and  at  2  12° 

. 

AUTHOEITY. 

42 
43 

44 
45 

46 

47 
'  48 
49 

50 

51 
52 
53 
54 
55 

56 
57 
58 
59 

60 
61 

62 
63 

64 
65 
66 
67 

68 

69 

70 

71 
72 
73 
74 
75 
76 
77 

78 
79 
80 
81 
82 
83 
84 

Canute    

16  c 

9.0 
11.37 
11.8 

12.23 
11.10 
16.04 
9.15 

9.24 
10.5 

15 

18 

13 
13 
12.5 
12 

17.4 

871 

831 

788 

1050 
974 

758 
736 
818 
802 

495 
688 

831 
1050 

779 

708 

920 
720 
707 
694 

1245 

54.4 

79 

75 
75 
75 

75 
75 
87.6 
92 
82.5 

62 
66.3 
51 
87.65 

53.6 
65.5 

55.4 
58.3 

77.9 

64.^3 

70.8 
55.4 
56.6 
57.8 

71.5 

42 
58 
coke 
46 
49 

54 

42 
57 
61 
45 

108 
57 
102 
66 
94 

44 
70 
38 
54 

84 
87 

coal 
62 
109 

119 
163 
119 
118 
111 

13i.6 
90.5 

coal. 
82.2 
69.6 
56.6 

74.7 
77.0 
Ib2.5 
80.7 

121.5 

94^8 
91.0 
115.5 
106.4 
93.3 

6.42 
8.89 

6.46 
7.19 

8.69 

7 
7.8 
9.2 
6.7 

11.6 
8.2 
14.1 
18.1 
10.3 

6.3 
6.8 
6.0 
7.2 

9.4 
10.0 

9.54 
9.56 

8.76 
9.13 

10.04 

12.46 
10.11 
11.31 
11.04 

8.09 
10.71 
9.52 
9.72 
8.15 

10.71 
9.32 
10.47 
9.94 

8.23 
8.57 

7.88 
6.6 

6.18 
6.07 
7.05 
6.46 
7.28 

5.70 
8.34 

6.66 
.      6.68 
6.61 
7.54 
5.64 
6.65 
7.28 

D.  K.  CJark. 

M 

u 
u 

Reports  M.  M. 
Assoc.  U.  S. 

D.  K.  Clark. 

14 
It 

R.  R.  Gazette. 

tt 
U 

"      

M 

Caledonian  R. 
No.  33  

No   42 

No.  43     .  . 

No.  51  

No.  13  

No   13 

No.  13  
No.  125,  127.... 
No.  102 

E.  A  G.  R. 
Orion  &  Sirius 
America  &  Nile 
Pallas 

Brindley  

G.  &  S  W.  R. 
Orion 

Queen 

P.  F.  W.  &  C.R. 

No    121 

No.  158  

Jeff.    Mad.    & 
Ind. 

No.  28  

No.  28 

No.7  

No  30 

B.  &  A.  R.  R. 
No.  129  

Coal.  Comb. 

6.17 
6.36       7.01 
7.31       7.92 
7.61       8.27 
6.69       7.48 
7.08       7.85 
7.53       8.17 

*> 

n 

No.  169  

« 

46 


STEAM  MAKING;    OR  BOILER  PRACTICE. 


Number  for  Refer- 
ence. 

NAME. 

Area  of  grate.  Sq.  ft. 

Area  of  heating  sur- 
face. S(i.  ft. 

Heating  surface  -r- 
grate  surface. 

ICoke  per  sq.  ft.  of 
grate  per  hr.  inlbs. 

Water  per  sq.  ft.  of 
grate  per  hour  in 
cubic'  ft. 

Pounds  water  evap- 
orated per  It),  fuel 
from  and  at  212° 

AUTHORITY. 

85 
86 
87 

88 
89 
90 

91 
92 
93 
94 
95 

96 
97 
98 
99 

100 
101 
102 
103 
104 

105 

106 
107 

108 
109 
110 
111 
112 
113 
114 
115 
116 
117 
118 
119 

No.  160  

17.4 
16 

15.1 
15.3 

13.1 

15.3 
13.1 

15.3 

12.5 
18.9 

1245 
1012 

899 
848 

846 

787 
801 
83d 

1141 

618 

71.5 
63.3 

59.6 
55.5 

64.6 

51.4 
61.3 
54.0 

91.2 
32.7 

86.3 
130.0 
114.9 

83.9 
171.8 
117.3 

109 
118 
115 
37 
105 

111 
113 
92 
96 

125 

200 
116 
171.5 
87 

109 
95 
71 

103 
111 
115 
130 
146 
127 
113 
111 
145 
113 
129 
133 

48.9 
62.2 
78'.  9 
96.0 

10.0 

Pittsburgh  best, 
poor 
Alabama 

Coal. 

8.01 
6.42 
6.67, 

8.36 
5.34 
7.30 

5.86 
5.08 
5.98 

8.48 
7.  VI 

6.48 
6.60 
7.44 
6.16 

5.78 
5.3 
6.96 
5.4 
6.94 

5.71 
5.75 
6.28 

8.77 
6.98 
7.68 
7.52 
6.47 
6.58 
7.60 
7.80 
6.11 
7.79 
7.24 
6.80 

8.88 
8.26 
7.94 

7.48 

Comb. 

8.64 
6.97 
7.25 

7.32 
7.52 
7.50 
10.60 
9.00 

8.1 
8.2 
9.3 

7.7 

7.2 
6.6 
8.4 
6.7 
8.6 

7.1 
7.2 
7.9 

R.  R.  Gazette. 
M.  M.  Ass'n. 

M 

Ml 

|< 

(I 

M 
U 

(1 
If 

No  150 

C.  H.  &  D. 

No  36 

H 

W.  St.  L.  &  P. 

No  180 

No  144 

i  80   hollow 
1     stay  bolts. 

No.  150... 

No.  159  
No.  171  

L.  &  N. 
No  255 

Torpedo  boat. 
Fan  draft. 

Tennessee  

Cent.  Kentucky. 

«             <( 
K             «» 

U                              It 

W.  Virginia....! 
E.  Kentucky  

CHAPTER      Ml. 

EXTERNALLY  FIRED  STATIONARY  BOILERS. 

Boilers  may  be  defined  as  the  closed  vessels  in  which  steam  is  gener- 
ated from  water  by  the  action  of  heat  applied  from  the  outside, — water  being 
introduced  at  one  aperture  and  steam  removed  at  another.  The  heat  is 
usually  the  heat  carried  in  the  products  of  combustion,  or  hot  gas  from  a 
furnace,  which  is  passed  along  the  surface  of  the  boiler  and  by  giving  its 
heat  to  the  material  of  the  boiler  first  heats  that  material,  that  again  heat- 
ing the  water  in  the  boiler. 

The  shapes  which  have  been  given  to  boilers  are  almost  endless  and  it 
is  not  our  intention  to  attempt  any  complete  collection  of  the  types  which 
have  been  used  and  abandoned,  or  are  still  being  experimented  with;  but, 
on  the  contrary,  our  aim  has  been  to  exclude  all  but  what  may  be  called 
the  standards,  such  as  have  been  used  for  years  with  satisfaction. 

Modern  boilers  are  usually  either  cylindrical,  or  a  combination  of  cylin- 
drical with  rectangular  forms.  The  material  is  either  wrought  iron  or  steel. 
Copper  is  still  used  in  the  fire-boxes  of  English  locomotives,  and  brass 
tubes  are  also  in  use.  The  strength  and  capacity  we  shall  discuss  later, 
and  at  present  content  ourselves  with  a  classification  and  brief  description 
of  the  standard  types. 

In  classifying  boilers  we  may  base  our  system  upon  their  use,  whether 
for  stationary,  locomotive,  or  marine  purposes,  and  this  gives  a  very  conve- 
nient division.  Stationary  boilers  may  be  divided  into  three  primary 
groups. 

First. — Cylinder  forms  with  the  fire  external  and  the  products  of  com- 
bustion also  external  to  the  cylinders. 

Second.— Externally  fired  boilers  with  fire  tubes,  by  which  the  products 
of  combustion  are  passed  through  the  water  or  steam. 

Third.— Internally  fired  boilers  in  which  the  furnace  is  inclosed  by  a 
water  chamber  on  all  sides  but  one  or  two,  and  the  products  of  combus- 
tion pass  through  tubes  surrounded  by  water. 

Locomotive  boilers,  including  with  them  portable  boilers,  are  usually  in- 
ternally fired,  having  a  rectangular  furnace  with  fire  tubes  passing  through 
a  horizontal  shell;  sometimes  portable  boilers  are  made  with  vertical 
cylindrical  shells  and  fire-boxes,  with  vertical  fire,  and  sometimes  also  with 
vertical  water,  tubes.  There  is  less  variety  in  locomotive  boilers  proper 
than  in  any  other  class;  with  marine  boilers,  on  the  other  hand,  the  mod- 
ifications have  been  almost  endless. 

The  types  of  marine  boilers  are  now  much  better  defined  and  may  be 
considered  as  established,  and  we  have  two  broad  divisions,  being  the 
practice  in  and  around  New  York  and  the  practice  on  the  Clyde. 


48  STEAM  MAKING;    OR,  BOILER  PRACTICE. 

Marine  boilers  were  for  many  years  after  their  first  introduction 
limited  to  low  pressures  on  account  of  their  being  fed  with  salt  water  from 
the  hot  well  of  an  injection  condenser,  and  as  long  as  the  pressure  was  not 
over  twenty  pounds  per  square  inch,  they  could  be  kept  clean  by  blowing 
out  and  washing;  with  a  higher  temperature,  the  water  deposited  salt  too 
rapidly  and  made  scale  too  fast.  On  the  Western  Rivers,  where  fresh 
but  very  bad  water  was  to  be  had,  the  use  of  the  condensing  engine 
was  soon  abandoned,  and  by  the  use  of  steam  at  pressures  exceeding  150 
pounds  per  square  inch,  a  very  simple  and  cheap  engine  and  boiler  were 
developed  which  is  at  least  as  economical  in  the  use  of  fuel  as  the  low  pres- 
sure condensing  engines  of  that  day.  The  practice  around  New  York  has 
remained  almost  stationary,  while  that  of  the  Clyde  with  the  introduction 
of  the  surface  condenser  began  at  once  raising  the  pressure  and  introdu- 
cing compound  engines,  until  in  1882  several  steamers  were  set  at  work 
with  125  pounds  pressure  per  square  inch,  and  the  magnificent  steamers 
of  the  Atlantic  lines  are  working  with  ninety  pounds.  The  introduction 
of  higher  pressures  required:  first,  stronger  boilers,  and  then  more  ac- 
cessible boilers  for  the  removal  of  harder  scale  and  for  more  perfect 
inspection;  and  the  Clyde  practice  gradually  grew  definite. 

The  North  River  Boiler,  as  the  New  York  type  is  called,  has  one  or  more 
rectangular  internal  furnaces  open  on  the  bottom  and  with  a  cast-iron  front; 
the  products  of  combustion  are  carried  through  large  tubes  to  a  connect- 
ing chamber  and  then,  ascending,  pass  back  in  smaller  tubes  to  the  front  of 
the  boiler  and  through  a  shell  of  steam  in  an  annular  chamber  around  the 
base  of  the  stack.  The  external  form  is  a  cylinder  with  a  rectangular  block 
inserted  at  the  bottom  of  one  end.  The  use  of  flat-stayed  surfaces  around 
the  fire  separates  this  type  from  the  Clyde  type,  which  uses  cylindrical 
furnaces  as  well  as  shell.  The  use  of  fire  tubes  of  large  diameter  has 
always  been  confined  to  the  English  practice,  and  in  this  country  we 
never  possessed,  until  very  recently,  the  facilities  for  manufacture  which 
their  usage  demands.  The  Clyde  boilers  may  be  classed  by  the  number 
of  furnaces,  from  one  to  four,  and  by  their  being  fired  from  one  or  both 
ends.  Locomotive  boilers  are  used  for  high  pressures  on  the  torpedo  boats, 
and  all  the  forms  of  upright  boilers  used  with  steam  fire  engines  have 
been  used  with  small  boats,  as  also  the  water  tubxi  types,  especially  that  of 
Herreschoff,  in  connection  with  surface  condensers. 

Externally  fired  boilers  are  usually  combinations  of  cylindrical  forms 
set  with  axes  either  horizontally,  vertically,  or  inclined.  Of  the  types  with 
horizontal  axis,  the  simplest  is  the  plain  cylinder  boiler  set  in  brickwork, 
either  singly  or  in  groups  of  two  or  more,  called  batteries.  The  only  ob- 
jections are  the  room  taken  up,  the  amount  of  land  occupied,  and  the 
quantity  of  brickwork,  with  its  liability  to  leak  air  into  the  furnace  and 
consequently  the  reduction  of  temperature  therefrom.  The  boiler  is  usually 
hung  from  overhead  supports  and  the  brickwork  held  in  place  by  tie  rods 
passing  over  the  boiler  connecting  vertical  bars  called  "buck  staves," 
these  act  as  anchor  plates  against  the  movement  of  the  links  outward 
under  the  action  of  heat. 


EXTERN  ALL  Y  FIRED  STA  TIONARY  BOILERS.  49 

The  advantages  of  the  single  cylinder  boiler  are  simplicity,  ease  of 
access  for  inspection  and  repairs,  strength,  durability,  and  low  cost  of 
construction,  which  render  this  class  of  boiler  well  adapted  to  hard, 
continuous,  and  high  pressure  work.  They  are  commonly  used  for  blast 
furnaces  where  land  is  cheap  and  it  is  desirable  to  keep  them  in  steam  for 
a  long  time.  They  are  usually  fired  with  the  waste  gas  from  the  blast  fur- 
nace, but  must,  of  course,  have  independent  grates  to  use  when  the  fur- 
nace is  cold  at  starting  or  "blowing  in;" — the  gas  when  turned  over  the 
existing  fire  and  supplied  with  enough  air  burns  freely. 

We  select  as  an  example  the  boilers  of  the  Meier  Iron  Company,  at 
Bessemer,  Illinois,  opposite  South  St.  Louis,  constructed  upon  the  follow- 
ing specifications.  There  are  five  batteries  of  two  boilers  each. 

SPECIFICATION  FOE  ONE  BATTEEY  OF  STEAM  BOILEKS    FOR  THE  MEIER 

IRON  COMPANY. 

Each  Battery  is  to  consist  of  two  plain  cylindrical  boilers  with  rounded 
ends,  one  steam  drum  and  two  mud  drums,  each  boiler  to  be  60  feet  long 
and  42  inches  in  diameter.  The  boilers,  drums,  legs,  and  other  parts  to 
be  built  and  suspended  according  to  the  drawings.  The  shells  of  boilers 
to  be  of  £-inch  iron  and  the  heads  of  i-inch  iron.  There  is  to  be  one  ellip- 
tical manhole  in  each  boiler  of  sixteen  (16)  and  ten  (10)  inches  diameters 
bound  with  a  wrought-iron  gasket  of  5-inch  by  f-inch  and  closed  with  a 
cast-iron  plate  and  bridge  held  down  on  a  lead  gasket  by  wrought-iron 
bolts.  The  centre  of  these  manholes  to  be  exactly  in  the  upper  middle 
lines  of  the  boilers  and  in  the  middle  of  the  fourteenth  sheet  from  the 
grate  end  of  the  boilers. 

No  Horizontal  seams  to  be  below  the  fire  tiles. 

Steam  Drum  to  be  24-inches  diameter,  shell  of  £-inch,  heads  of  |-inch 
boiler  iron,  legs  of  |-inch  iron.  There  is  to  be  a  manhole  in  one  end, 
ellilptical,  10-inches  and  14^-inches  diameters  fitted  up  and  closed  like  those 
in  the  boilers.  There  are  to  be  two  mud  drums,  24  inches  diameter.  Shells 
of  | -inch  boiler  plate.  Heads  of  1^-inch  cast-iron.  Each  to  have  a  man- 
hole at  one  end  of  same  size,  and  fittings  as  on  the  steam  drum. 

Below  the  manhole  in  the  mud  drums  there  is  to  be  a  blow-off,  or  mud 
valve,  4  inches  in  diameter.  The  other  end  of  each  mud  drum  is  to  have  a 
4-inch  check  valve,  with  flange  for  attaching  to  the  feed  pipe.  Each  bat- 
tery is  to  be  suspended  in  four  places  by  bolts  and  supports  consisting  of 
channel  bars  carried  on  rails  as  shown  in  the  drawings,  and  the  boiler- 
maker  shall  erect  these  supports  and  suspend  the  boilers. 

The  plate  iron  of  the  boilers  and  drums  throughout  is  to  be  all  C.  H. 
No.  1.,  with  maker's  brand  designating  the  quality  stamped  upon  each 
sheet,  and  each  sheet  must  be  guaranteed  to  have  a  tensile  strength  of  fifty 
thousand  (50,000)  pounds  per  square  inch.  The  Meier  Iron  Company  to 
have  the  right  to  require  clippings  of  any  sheet  made,  for  the  purpose  of 
testing  the  same. 

The  boilers  when  fitted  to  be  tested  to  100  pounds  per  square  inch  of 
hydrostatic  pressure.  ( 


EXTERNALL  Y  FIRED  STA  TIONARY  BOILEMS. 


TBANSVEESE  SECTIONAL  VIEWS. 

SPECIFICATIONS  FOE  FITTINGS  FOE  BOILEES  FOE  MEIEE  IRON  COMPANY. 

I.  Safety  Valves. — There  is  to  be  one  on  each  steam  drum  of  4  inches 
clean  diameter  and  to  have  a  lever  and  weight  to  counter-balance  seventy- 
five  pounds  per  square  inch  pressure. 

II.  Steam  Valves. — One  8-inch  globe  valve  for  each  battery  of  boilers 
attached  by  means  of  flanges  and  bolts  to  the  cast-iron  pipes  between 
steim  drums  and  20- inch  steam  pipe. 

III.  Blow-off  on  Mud  Valves.— One  4-inch  valve  for  each  mud  drum 
attached  to  a  neck  and  flange  cast  on  the  head  of  the  drums. 

IV.  Glass  Tube  Water  Gauges.— One  to  each  boiler  so  arranged  that 
the  glass  tube  can  be  removed  or  replaced  while  the  steam  is  on  the  boiler. 
Tubes  12-inches  by  |-inch  best  Scotch  glass,  fittings  to  be  screwed  into 
one  head  of  the  boiler. 

V.  Mississippi  Gauge  Cocks. — Three  to  each  boiler  in  the  head,  to  be 
hereafter  designated   by  the  Meier   Iron    Company.      Shank  one  inch 
diameter. 

VI.  Steam  Whistle. — One  5-inch  whistle  placed  on  the  main  steam 
pipe  at  a  point  to  be  hereafter  designated. 

VII.  Steam  Gauges. — Two  John  Kupferle  &  Company  steam  gauges, 
7-inch  face  for  pressures  up  to  150  pounds  per  square  inch,  brass  casings 
with  syphon  pipes  carefully  tested.    One  of  these  to  be  placed  on  the  20- 
inch  steam  pipe  and  one  in  the  engine-house  at  points  to  be  hereafter 
designated. 

VIII.  Check  Valves. — One  4-inch  check  valve  with  flange  to  attach 
feed  pipe  for  each  mud  drum.    All  the  above  pieces  to  be  of  the  best  ma- 
terial and  workmanship,  all  joints  perfectly  steam  and  water  tight,  and 
subject  to  inspection  by  the  experts  of  the  Meier  Iron  Company.    The 
contractors  to  fit  up,  fasten,  and  erect  all  parts  ready  for  service. 


Accepted  by. 


The  shells  are  made  with  taper  rings  thus  making  the  outside  lap 
always  at  the  rear  end  of  the  sheet.     The  boilers  are  set  in  a  straight  flue 


52 


STEAM  MAKING;    OR,  BOILER  PRACTICE. 


EXTERN  ALL  Y  FIRED  STA  TIONAR  Y  BOILER&.  53 

with  a  fire  brick  lining.  There  is  a  combustion  chamber  in  front  of  each 
boiler  where  the  gas  from  a  60-inch  overhead  pipe  receives  air  through 
side  openings  in  the  chamber,  and  is  ignited.  Two  fire-brick  bridges  were 
added  afterwards.  The  flue  is  floored  with  red  brick  and  the  mud  drums 
are  protected  from  the  flame  by  fire-brick  arches  open  through  the  side 
walls.  The  rear  end  of  the  flue  connects  with  an  underground  flue  to  a 
stack  204  feet  high  and  10  feet  6  inches  diameter  of  opening  at  the  top. 

These  boilers  were  designed  by  Mr.  E.  D.  Meier,  a  member  of  the 
Board  of  Direction. 

In  point  of  simplicity  and  durability  a  combination  of  two  shells  comes 
next,  and  our  example  is  taken  from  the  boilers  at  the  works  of  the  "Nova 
Scotia"  Iron  Company,  near  Cuba,  Missouri. 

There  are  two  batteries  of  three  boilers  each,  side  by  side,  fired  by  gas 
from  the  furnace.  Each  boiler  is  carried  on  the  front,  and  by  six  sets  of 
slings,  and  consists  of  two  shells  one  over  the  other. 

The  upper  shell  is  40£  inches  in  diameter  and  55  feet  8  inches  long,  and 
the  lower  shell  is  30  inches  diameter  and  45  feet  8  inches  long.  The  shells 
are  16^  inches  apart  and  are  united  by  nine  13-inch  legs  with  cap  flanges  5 
feet  4  inches  from  centre  to  centre.  The  back  ends  of  upper  and  lower 
shells  are  in  the  same  vertical  plane,  and  the  lower  one  being  10  feet  shorter 
than  the  upper,  leaves  a  combustion  chamber  at  the  front  end. 

The  slings  are  made  by  a  4-inch  tee-iron  riveted  on  the  upper  side  of 
the  shell,  forming  nearly  a  semi-circle,  and  three  bolts  1-inch  diameter  with 
nut  at  the  lower  end  and  thread  and  nut  at  the  upper.  These  are  passed 
between  two  10-inch  I  beams  which  rest  on  cast-iron  "buck  staves"  built  in 
the  side  walls. 

The  metal  is  all  |-inch  in  thickness. 

When  there  are  two  or  three  smaller  lower  cylinders  in  place  of  the 
one,  the  boiler  is  known  in  England  as  the  "French"  or  "Elephant"  boiler, 
and  is  called  in  France  "Chaudiere  a  Bouilleurs,"  or  boiler  with  heaters, 
the  latter  term  being  applied  to  the  smaller  lower  cylinders.  The  ob- 
jections to  these  combinations  is  the  weakening  of  the  larger  shell  by 
the  openings  for  the  legs,  and  the  straining  action  produced  by  unequal 
expansion;  but  as  the  metal  used  is  very  thin,  the  boilers  are  very  durable. 
The  only  example  we  know  of  in  the  United  States  of  the  French  boiler  is 
a  small  one  with  two  "heaters"  which  had  been  in  use  for  nineteen  years 
at  the  shops  of  the  St.  Louis,  Alton  &  Terre  Haute  Bailroad  Company,  in 
East  St.  Louis.  The  service  was  very  moderate,  but  in  that  period  the 
only  care  taken  was  to  wash  out  once  a  week.  The  metal  was  ^  inch  in 
thickness  and  the  shells  were  not  over  30  inches  and  10  inches  diameter,  if 
our  memory  is  correct. 

The  "French"  boiler  tried  at  Mulhouse  at  the  Works  of  the  Socie'te 
Alsaciennes  des  Constructions  Mechanique,  in  1875,  by  a  Committee  of  the 
Socie'te  Industrielle  de  Mulhouse,  was  of  the  following  dimensions:  Shell, 
29  feet  6§  inches  long,  by  3  feet  8&  inches  diameter  by  |-inch  thick,  in 
eight  rings,  with  rounded  heads,  0^  inch  thick.  Heaters,  were  three  in 
number,  each  32  feet  9|  inches  long  by  19 /5  inches  diameter,  by  0^%  inch 


END    ELEVATION. 


TKANSVEKSE    SECTION. 


thick,  each  connected  by  three  legs  about  14  inches  diameter.  Those  for 
the  inner  heater  are  about  12  inches  long  and  those  for  the  outer  heaters 
about  21  inches  long  on  the  centre  line. 

The  grate  is  4  feet  $-.fa  inches  wide  by  4  feet  9j3g  inches  long,  of  which 
6/g  inches  is  over  the  bearing  bars.  The  effective  length  being  4  feet  2^ 
inches,  giving  an  area  of  20 j°<^  square  feet.  The  heating  surface  is  as 
follows: 

Square  feet. 

Main  shell 199.5 

Heaters 385.7 

Legs 22.4 

Total 607.6 

The  products  of  combustion  pass  first  from  the  grate  over  a  low  bridge 
along  the  "heaters,"  then  returns  to  the  front  on  one  side  of  the  shell,  and 
returns  to  the  rear  along  the  other  side  of  the  shell. 

The  only  thing  we  note  is  the  great  thickness  of  the  plates  used, 
which,  with  bad  water  foaming,  causes  much  scale  to  invite  burning.  The 
United  States  law  thus  limits  the  thickness  of  plates  exposed  to  the  direct 
action  of  the  fire  for  steamboat  boilers:  externally  fired  to  Oj^B0  inch,  and 
as  such  boilers  are  frequently  found  in  excellent  order  after  20  years  of  ser- 
vice, with  pressures  exceeding  100  pounds  per  square  inch  on  shells  42 
inches  in  diameter,  single  rivetted,  there  seems  little  use  in  making  them  £- 
inch  thick  to  carry  70  pounds  or  so  per  square  inch.  Our  illustration  shows 
this  boiler  and  setting. 

From  the  "French"  to  the  water  tube  boilers  is  a  natural  transition, 
the  water  cylinders  growing  smaller  and  more  numerous  till  the  well  known 
Howard,  Belleville,  Koot,  Kelly,  Firminich,  Perkins,  Babcock  &  Wilcox, 
and  Heine  boilers  were  introduced.  In  most  of  these  the  greater  com- 


EXTEENALL  Y  FIRED  STA  TIONA E  Y  BOIlfEES.  57 

plexity  of  arrangements  for  cleaning  seem  to  balance  any  advantages  they 
may  have  in  circulation,  and  the  leakage  at  the  innumerable  joints  goes 
far  to  neutralize  any  gain  made  by  the  higher  steam  pressure  which  can 
undoubtedly  be  carried  with  safety. 

Of  the  many  varieties  of  the  water  tube  type  we  select  as  example  one 
from  the  circular  of  the  Babcock  &  Wilcox  Company. 

The  Babcock  &  Wilcox  boilers  consist  of  inclined  sets  of  tubes  con- 
nected  at  each  end  by  steel  castings  into  which  the  tubes  are  expanded: 
the  front  and  upper  ends  are  connected  into  a  longitudinal  drum.  The 
rear  ends  are  connected  by  inclined  pipes  to  the  same  drum,  while  at  the 
bottom  there  is  a  mud  drum  of  cast-iron. 

There  are  hand  holes  opposite  each  end  of  each  tube  and  man  heads 
on  the  steam  and  mud  drums.  The  hand  hole  plates  are  milled  to  metal 
contact  with  the  connections  and  the  whole  section  is  hung  from  overhead 
by  bolts  carried  on  cross-beams  resting  on  the  walls.  The  products  of 
combustion  are  carried  three  times  across  the  tubes  by  means  of  deflectors 
and  these  from  all  the  different  batteries  are  carried  through  the  pipes  of 
an  "economiser,"  or  feed-heater,  on  their  way  to  the  stack. 

In  Heine's  boiler  the  connections  at  the  front  and  back  ends  of  the 
tubes  are  flat-stayed  wrought- iron  plates,  the  stay  bolts  are  made  hollow 
and  plugged;  by  taking  out  the  plugs  the  outside  of  the  water  tubes  may  be 
cleaned.  There  are  hand  holes  and  plates  opposite  each  end  of  each  tube. 
The  inclination  of  the  tubes  is  not  so  great  as  in  the  other  boiler.  There 
are  many  other  varieties  of  the  water  tube  boiler,  from  the  single  coil  of 
Jacob  Perkins,  used  with  a  "separator"  and  circulator  by  John  Elder,  and 
afterwards  revived  by  Herreschoff,  to  the  network  or  cage  of  tubes  used  by 
Loftus  Perkins. 

A  very  long  time  ago  the  device  of  an  internal  flue  was  introduced  to 
increase  the  heating  surface  without  increase  of  ground  room,  and  an  ad- 
vantage was  at  once  gained  thereby, — that  with  less  water  and  more  surface, 
steam  could  be  raised  more  quickly:  at  first  a  single  tube  was  used,  then 
two  or  more  of  smaller  diameter,  till  finally  the  multi-tubular  boiler  pro- 
vided great  heating  surface  within  moderate  space. 

Of  the  externally  fired  boilers  with  return  fire  tubes,  or  flues,  the  use  of 
a  single  return  flue  is  not  common  in  the  United  States,  and  we  have  no 
knowledge  of  their  use  except  in  some  cases  where  the  waste  heat  of 
puddling  furnaces  has  been  utilized;  also  a  few  which  went  out  of  service 
twenty  years  ago. 

Horizontal  externally  fired  return  flue  boilers,  with  from  two  to  twelve 
flues,  are  the  almost  universal  boiler  of  the  Mississippi  Valley,  a  natural 
consequence  of  their  use  upon  the  rivers  for  steamboats,  and  we  shall 
consider  them  here  as  stationary  boilers. 

The  chief  restrictions  upon  the  construction  of  boilers  for  use  in  steam- 
boats upon  the  Mississippi  River  and  tributaries  are  as  follows: 

1.  Boilers  must  be  tested  at  least  once  a  year  by  hydrostatic  pressure 
and  the  test  applied  must  exceed  the  working  pressure  allowed  in  the  ratio 
of  three  to  two. 


58  STEAM  MAKING;  OR,  BOILER  PRACTICE. 

2.  Fire  line  must  be  kept  at  least  2  inches  below  low  water  line. 

3.  Water  level  must  be  kept  not  less  than  4  inches  over  flue. 

4.  Feed-water  must  be  so  delivered  as  not  to  injure  boiler  when  enter- 
ing it. 

5.  Fusible  plugs  must  be  placed  in  such  position  as  to  melt  when  water 
gets  too  low. 

6.  Boilers  42  inches  in  diameter  and  £-inch  shell  may  be  allowed  a 
working  pressure  of  150  pounds  per  square  inch  and  the  pressure  allowed 
for  other  diameters  and  thickness  may  vary  inversely  as  the  diameter  and 
directly  with  the  thickness.    If  double  rivetted  longitudinal  seams  are 
used  the  pressure  allowed  is  20  per  cent.  more. 

7.  Each  plate  must  be  stamped  with  the  number  of  pounds  tensile 
strain  it  will  bear. 

8.  The  working  pressure  allowed  must  not  exceed  one-sixth  of  the 
tensile  strain  of  the  sheets,  unless  the  longitudinal  seams  are  double 
rivetted,  in  which  case  20  per  cent,  additional  may  be  allowed. 

9.  The  plates  of  externally  fired  boilers  exposed  to  the  action  of  heat 
must  not  be  over  Oj^%  inch  thick. 

10.  The  flues  or  tubes  of  externally  fired  boilers  must  have  not  less  than 
3  inches  clear  space  between  and  around  them. 

For  the  two-flue  type  we  select  the  boilers  of  the  river  steamer 
"Montana,"  as  described  by  Mr.  Wm.  H.  Bryan,  Mechanical  Engineer,  of 
St.  Louis,  Mo. : 

The  boilers  are  four  in  number,  set  in  one  battery.  They  are  each  42 
inches  diameter  and  26  feet  long,  with  two  flues,  each  15  inches  diameter. 
They  are  of  C.  H.  No.  1  iron,  and  were  built  by  D.  W.  C.  Carroll,  of  Pitts- 
burgh, Pa.  The  shell  is  of  0T2565  wrought-iron  in  sheets  24  inches  wide  and 
1  inch  lap  on  circumferential  seams,  single-rivetted  If -inch  centres;  longi- 
tudinal seams,  double  rivetted  Ig-inch  centres,  rows  If  inches  apart.  Heads 
of  i-inch  iron,  C.  H.  No.  1.  Flange  3  inches  inside  shells,  rivets  If  centres. 
Steam  drum  is  20  inches  diameter  by  15  feet  long,  and  connects  with  eaeh 
shell  by  a  14-inch  leg.  Centre  of  drum  37  inches  above  centre  of  shells. 
Back  head  flanged  in  for  flues.  Front  end  flanged  outward  for  same. 
Shell  sheets  alternately  lap  in  and  out,  making  laps  all  toward  after  end. 
Flues  all  lap  same  as  shells,  thus  the  gas  never  strikes  fair  on  a  caulked 
edge.  Flues  of  |-inch  iron  15  inches  diameter  and  centre  of  flues  18  inches 
apart  and  3£  inches  below  centre  of  boiler.  One  manhole  9|  inches  by  15 
inches  above  flues  at  after  end  of  each  boiler:  its  lower  edge  is  13£  inches 
from  top  of  boiler  and  i-inch  below  low  water  line.  Manhole  strengthened 
by  f -inch  ring  inside.  Manhead  plate  of  cast-iron  with  two  arch  bars. 
Hand- hole  4  inches  by  6  inches  in  front  head,  lower  edge  2  inches  from 
bottom.  Heads  stayed  to  shell.  There  are  two  mud  drums,  one  under 
second  sheet  from  after  end  and  one  under  fifth  sheet  from  front  end. 
Steam  drum  over  fifth  sheet  from  after  end.  Feed  water  introduced  at 
after  drum.  Mud  drums  are  16J  inches  inside  diameter  and  15  feet  long, 
with  centre  41  inches  below  centre  line  of  boiler,  united  to  each  shell  by  8- 


EXTERN  A  LL  Y  FIRED  8  TA  Tl  ON  A  R  T  BOltERS.  59 

inch  legs.  Steam  is  taken  from  steam  drum  by  a  6-inch  copper  pipe. 
Safety  valve  on  each  boiler  with  area  11  square  inches.  Lever  is  4  feet  3 
inches  long,  notched  at  intervals.  Weight  is  9£  inches  by  9£  inches  by 
8  inches  and  weighs  200  pounds.  Blows  off  at  140  pounds  per  square  inch 
and  sets  weight  at  31  inches  from  fulcrum.  One  pressure  gauge  is  placed 
at  the  front  of  the  boilers  and  one  near  the  engines.  There  are  10  gauge 
cocks  on  the  four  boilers  and  each  boiler  has  a  float  gauge  with  outside 
dial.  These  are  at  the  after  end  of  the  boiler  close  to  the  feed  pump  and 
are  under  the  eye  of  the  engineers  on  watch. 

The  front  end  of  the  boiler  is  carried  by  the  cast-iron  front.  A  3-inch 
by  £-inch  ring  is  rivetted  on  the  shell  and  rests  on  the  front.  The  other 
end  of  the  boilers  is  carried  on  the'back  mud  drum,  which  rests  on  cast- 
iron  supporting  blocks. 

The  furnace  is  14  inches  in  height  from  the  grate  bars  to  the  shell  and 
37  inches  high  between  boilers;  it  is  17  feet  wide  under  all  four  shells,  6^ 
feet  long  to  top  of  bridge  wall  and  is  built  with  fire  brick  throughout.  The 
grate  is  17  feet  wide  by  4  |eet  2  inches  long  and  70.8  square  feet  in  area. 
The  bars  are  double,  of  cast-iron,  with  1-inch  air  spaces  between  the  pair 
of  bars,  and  with  ^-inch  lugs,  giving  the  same  space  to  the  next  bar.  The 
top  of  grate  is  2  inches  below  lower  lining  of  fire-door.  The  doors  be- 
tween shells  are  18  inches  wide  by  14  inches  high,  with  half  doors  12  inches 
wide  and  13  inches  high  on  outer  side  of  outer  shells.  The  doors  are  of 
cast-iron  with  ^-inch  holes  and  the  front  is  of  cast-iron,  in  pieces,  bolted 
together,  and  lined  with  fire-brick.  The  ash  pit  is  18  inches  below  bars 
and  the  same  area  as  the  grate.  The  drip  from  the  long  exhaust  pipe  is 
run  in  here  to  put  out  the  fire  and  cool  the  ashes  which  fall  through  the 
bars.  The  ash-pit  doors  are  of  sheet-iron,  three  large  and  two  small  ones. 
The  fire  bridge  wall  is  11  inches  in  height  with  a  slope  up  from  the  grate 
thereto,  a  run  horizontally  of  2  feet,  carried  with  the  rear  end  of  the  grate 
by  a  special  frame.  The  flame  chamber  slopes  from  the  bridge,  where  it 
is  3  inches  below  the  shell,  to  the  rear  end,  where  it  is  6  inches  below. 
There  is  a  lining  of  4-inch  red  brick  set  in  and  covered  by  clay,  and  the 
side  walls  are  made  in  the  same  way,  carried  in  a  sheet-iron  casing,  and 
supported  from  the  deck  by  iron  rods. 

The  stacks  are  two  in  number,  each  3  feet  in  diameter,  and  55^,  feet 
above  the  grate,  and  are  of  No.  12  iron.  The  "breeching"  or  smoke  connec- 
tion is  of  the  same  thickness,  and  is  provided  with  doors  opposite  the  flues 
in  each  boiler. 

The  proportions  and  dimensions  are  summed  up: 

Grate  area 70.8  square  feet. 

Total  heating  surface 1431 . 2 

Ratio,  about 20  to  1 

Calorimeter 9.82 

Grate  area  to  Calorimeter 7.2 

Area  stacks 14.14 

Grate  area  to  stack  area 4. 6 

Steam  room. 662  cubic  feet. 

Water  room -..      294 

"     2208  gallons  (U.  S.) 


EXTERN  ALL  Y  FIRED  8  TA  TIONA  R  Y  SOBERS. 


61 


L  A* 

Through  G  H     I  Through  E  T 
Furnace  Sections 


BOILERS   OF  THE   "MONTANA' 


BOILERS   AT   THE    LA  CLEDE    ROLLING    MILL, 
ST.  LOUIS,    MO.-Elevation. 


62 


STEAM  MAKING;  OR,  BOILER  PRACTICE. 


EXTERNAL  L  Y  FIRED  STA  TIONAR  Y  BOILERS.  63 

Weight  of  boilers,  etc 29263  pounds. 

Weight  of  water 18350 

Weight  of  stacks 2357 

Weight  of  grate 5700       " 

Total 55671 

Next  in  point  of  simplicity  come  boilers  with  four  flues,  and  we  take 
as  an  example  four  boilers  built  in  1881  for  the  Laclede  Rolling  Mill,  St 
Louis,  which  were  built  under  the  following  specification: 

SPECIFICATION  FOR  A  BATTERY  OF  FOUR  BOILERS  FOR  LACLEDE 
ROLLING   MILL. 

ST.  Loais,  Mo.,  Aug.  i,  1881. 

Shells. — The  shell  to  be  of  the  best  hammered  charcoal  iron,  48  inches 
diameter,  26  feet  long,  and  |-inch  thick,  and  to  have  a  tensile  strength  of 
55,000  pounds  per  square  inch.  All  longitudinal  seams  to  be  above  the  fire 
line  and  double  rivetted.  Seams  to  be  staggered  to  prevent  a  continuous 
row  of  rivets. 

Heads. — Heads  to  be  of  the  best  hammered  charcoal  flange  iron,  and 
to  be  f -inch  thick.  The  back  head  of  each  boiler  to  contain  an  11  inch  by 
15-inch  man-hole,  and  the  front  head  a  4-inch  by  6-inch  hand-hole. 

Flues.— Each  boiler  to  have  two  12-inch  flues  and  11-inch  flues,  as 
shown  on  drawing.  Flues  to  be  of  |-inch  iron  and  of  same  quality  as  shell. 

Steam  Drum.-  -The  steam  dimrn  to  be  30  inches  in  diameter  and  the 
length  equal  to  the  width  of  the  battery  of  boilers.  The  legs  of  steam 
drum  to  be  10  inches  diameter  and  8  inches  long.  Each  end  of  steam  drum 
will  contain  an  11-inch  by  15-inch  man-hole.  The  iron  used  for  steam 
drum  and  legs  to  be  £-inch  thick  and  of  same  quality  as  that  used  in  shells. 
Legs  to  be  attached  by  cap  flanges. 

Mud  Drum. — The  mud  drum  to  be  at  back  end  of  boilers,  as  shown  on 
drawing,  and  to  reach  the  entire  width  of  the  bottom.  Diameter  of  drum 
to  be  18  inches,  and  of  same  quality  of  iron  as  shell.  Legs  to  be  8  inches 
diameter  and  attached  by  cap  flanges.  Thickness  of  iron  for  mud  drums 
and  legs  j^-inch.  Length  of  legs,  20  inches.  Each  end  of  mud  drum  will 
contain  a  10-inch  by  14-inch  man-hole  and  one  end  to  be  furnished  with  a 
3-inch  brass  blow-off  cock.  Heads  of  mud  drum  f -inch  thick. 

Supports  Jor  Boilers. — The  front  ends  of  boilers  will  rest  on  fire  front 
and  the  back  ends  will  rest  on  cast-iron  stands. 

Safety  Valves. — There  will  be  two  4^-inch  safety  valves,  one  near  each 
end  of  steam  drum,  and  fitted  with  proper  weights  and  levers  for  a  pres- 
sure of  100  pounds  steam.  The  chests  to  be  of  cast-iron,  the  valves  and 
seats  of  composition,  as  per  drawing. 

Dry  Pipes. — A  dry  pipe  7^-inches  diameter,  and  8  ft.  long  to  be  placed 
in  each  boiler  near  the  top.  The  top  of  dry  pipe  will  be  drilled  with  holes 
§-inch  diameter,  equally  distant  apart;  aggregate  area  of  holes  to  be  twice 
the  area  of  the  pipe. 

Stop  Valve. — One  12-inch  iron  globe  valve  with  outside  screw  steam 
valve  and  seat  to  be  of  brass,  to  be  secured  to  steam  drum  by  flanges. 


64  STEAM  MAKING;   OR,  BOILER  PRACTICE. 

Gauge  Cocks. — Three  |-inch  Mississippi  gauge  cocks  to  be  placed  in 
back  end  of  wing  boiler. 

Glass  Water  Gauges.— One  glass  tube  water  gauge,  to  be  placed  in  the 
front  end  of  each  wing  boiler. 

Breeching. — The  breeching  to  be  of  No.  12  iron,  with  doors  opening 
upwards,  provided  with  hinges  and  latches. 

Boiler  Front. — The  fire  front  will  have  tight-fitting  fire  and  ash  pit 
doors,  with  suitable  hinges  and  latches.  Registers  and  perforated  lining 
onfire  doors,  as  per  drawing.  Top  of  grate  bars  30  inches  below  boilers. 

Stack.— The  stack  will  be  60  feet  high  above  breeching,  and  4  ft.  6  in. 
diameter, with  damper  above  breeching* 

Man-holes. — The  man-holes  to  be  11  x  15  inches,  each  man-hole  to 
have  around  it  on  the  inside  an  elliptic  ring  of  iron  2£  x  f  inch.  Eivets  to 
be  countersunk  flush  on  both  sides.  Parts  where  gasket  joint  comes  to 
be  faced.  Man-hole  plates  to  be  of  cast-iron,  and  secured  by  wrought- 
ron  arches  and  bolts.  A  2  x  £  inch  wrought  iron  ring  on  outside  of  hand- 
holes. 

Steam  Gauge. — One  Ashcroft's  steam-gauge,  8-inch  face. 

Bearing  Bars. — Bearing  bars  to  be  furnished  as  per  drawing.  Grate 
bars  to  be  furnished  by  company. 

No  paint  or  putty  is  to  be  put  on  any  part  of  boilers  until  the  same 
have  been  delivered  and  tested  at  the  works.  Only  first-class  workman- 
ship will  be  accepted. 

The  setting  of  these  boilers  is  in  red  brick,  lined  with  fire  brick.  There 
are  two  bridges,  and  air  is  admitted  through  the  rear  bridge  to  the  com- 
bustion chamber,  which  is  rather  peculiar  in  form. 

Boilers  with  five  flues  are  very  much  used  in  the  Valley  of  the  Missis- 
sippi River,  but  there  is  little  difference  between  them  and  those  last 
described. 

What  is  known  as  a  compromise  between  flue  and  tubular  boilers,  is 
one  with  6-inch  lap-welded  tubes.  Of  this  class,  we  give  as  an  example,  a 
battery  of  three  boilers  at  the  works  of  the  St.  Louis  Lead  and  Oil  Com- 
pany, St.  Louis.  These  boilers  are  each  42  inches  diameter,  and  22  feet 
long.  Shells  of  £-inch  thick  C.  H.  No.  1  iron,  single  riveted.  Each  boiler 
has  eight  6-inch  lap-welded  tubes,  with  steam  and  mud  drums,  as  shown 
in  the  drawing,  which  requires  no  further  explanation.  The  heads  are 
flanged  and  the  flues  riveted  thereto. 

As  an  example  of  the  4-inch  tubular,  we  describe  three  boilers  designed 
by  us  for  Washington  University,  and  erected  in  1879.  They  are  set  inde- 
pendently and  are  used  mainly  for  heating. 

Each  boiler  is  60- inches  diameter,  and  16  feet  long,  with  36  lap- welded 
tubes,  4-inches  external  diameter  arranged  in  two  groups,  with  a  central 
gangway  12  inches  in  the  clear  in  the  centre  of  the  boiler.  This  space 
allows  circulation  and  complete  inspection,  with  convenience  in  cleaning. 
The  shell  is  £-inch  steel,  the  heads  J-inch  steel  with  tensile  strength  of 
70,000  pounds  per  square  inch.  The  shell  is  supported  by  the  front  be- 


EXTERNALLY  FIRED  STATIONARY  BOILERS. 


65 


1 1 1 1 1 1 1 1 1 1 1 1 1  1 1 1 1  M  i  ri"1"^ 

/  i  i  '  I  I  i  i  I  I  I  i  I  I  I  I  I  I  !  I  i  j.       I 


66 


STEAM  MAKING;  OR,  BOILER  PRACTICE. 


EXTERN  ALL  Y  FIRED  STA  TIONARY  BOILERS. 


67 


So'tlc    1 


Feet 
Metres 


NOTE.— This  scale  also  applies  to  cuts  on  pages  65  and  66. 

END  AND  SECTIONAL  VIEWS. 
BOILEKS   AT   WOKKS    OF    ST.  LOUIS   LEAD    &    OlL    CO.,    ST.  LOTJIS,    MO. 


yond  which  it  projects  enough  to  attach  the  bottom  blow-off.  There  is 
neither  dome  nor  mud  leg.  Steam  is  taken  by  a  6-inch  sheet  iron  dry  pipe. 
The  heads  are  stiffened  and  braced  in  the  manner  shown.  We  suggest  as 
an  improvement  that  the  dry  pipe  be  taken  from  the  top  of  the  back  head, 
and  that  the  safety  valve  be  connected  thereto.  By  so  doing,  no  open- 
ing need  be  made  in  the  shell.  All  longitudinal  seams  are  double- 
rivet  fced.  The  depth  of  furnace,  40  inches  from  shell  to  grate  bar,  has 
been  much  criticized,  but  it  has  answered  very  well. 

All  sorts  of  devices  for  smoke  prevention,  by  the  admission  of  air,  etc., 
have  been  tried  on  this  furnace,  and  the  conclusion  reached  is  that  an  in- 
telligent fireman,  with  a  moderate  amount  of  work,  will  do  more  to  pre- 
vent smoke  than  anything  else;  but  that  crowded  as  these  boilers  often 
are  there  is  no  way  to  prevent  smoke. 


68 


STEAM  MAKING;  OR,  BOILER  PRACTICE. 


The  use  of  a  central  space  for  circulation  is  quite  frequent,  but  it  is 
usually  not  more  than  5  or  6  inches.  In  most  cases,  however,  the  boiler  is 
stuck  as  full  of  tubes  as  it  can  be,  and  they  are  placed  so  close  to  the  shell 
that  straining  and  grooving  occur  from  the  unequal  expansion. 

We  illustrate,  as  conforming  more  closely  to  the  usual  practice,  a  60- 
inch  boiler  designed  by  the  Hartford  Boiler  Inspection  and  Insurance 
Company. 

In  some  cases  the  products  of  combustion  are  taken  over  the  shell 
after  coming  through  the  tubes.  The  use  of  domes  upon  the  top  of  shell  is 
almost  universal,  but  there  are  objections  to  them  which  will  be  given 
later. 

Very  many  compounds  of  these  simple  types  have  been  made.  The 
French  boiler  is  often  used  with  fire  tubes  in  the  upper  shell,  and  a  com- 
bination of  two  short  cylinders,  the  lower  and  larger  full  of  tubes,  while 
the  upper  and  smaller  is  used  as  a  steam  drum.  This  is  introduced  by 
the  name  of  "compound  boiler;"  but  as  this  name  is  used  for  many  other 
forms,  it  is  hardly  distinctive. 


SECTIONAL  ELEVATION. 

60- INCH  HORIZONTAL  TUBULAR  STEAM  BOILER.    DESIGNED  BY  HARTFORD 
STEAM  BOILER  INSPECTION  &  INSURANCE  Co. 

SPECIFICATION 

For  QQ-inch  Horizontal  Tubular  Steam  Boiler,  Prepared  by  The  Hartford 
Steam  Boiler  Inspection  and  Insurance  Company. 


TYPE. 


Boiler  to  be  of  the  Horizontal  Tubular  type,  with  Over- 
hanging  Front  and  Doors  complete. 


EXTERN  A  LLY  FIRED  STA  TIONARY  BOILERS. 


69 


tCTION  OF   WALL  THROUGH  C-D  ON  FRONT  ELEVATION 

---------------  S.--I9-2"  .................... 


PLAN. 


TBANSVEBSE  VIEWS. 


DIMENSIONS.       j  Boiler  to  be  16  ft.  3  in.  long  outside,  and  60  in.  in  dia- 
meter.   Tube  heads  to  be  15  ft.  apart  outside. 


TUBES. 

How    SET    AND 


Boiler to  contain  66  best  lap-welded  tubes,  3  in.  in 

diameter  by  15  ft.  long  set  in  vertical  and  horizontal 


FASTENED.         rows,  with  a  space  between  them,  vertically  and  horizon  - 
I  taUy,  of  not  less  than  one  inch  (1"),  except  the  central  ver- 


70 


STEAM  MAKING;  OR,  BOILER  PRACTICE. 


tical  space,  which  is  to  be  two  inches  (2")»  as  shown  in 
drawing.  No  tube  to  be  nearer  than  3  in.  to  shell  of  boiler. 
Holes  through  heads  to  be  neatly  chamfered  off.  All 
tubes  to  be  set  by  a  Dudgeon  Expander,  and  slightly 
flared  at  the  front  end,  but  turned  over  or  beaded  down 
at  back  end. 

FOR  IRON  PLATES. 
QUALITY  AND       Shell  plates  to  be  f  of  an  inch  thick,  of  the  best  C.  H. 
THICKNESS  OF  No.  1  iron  with  brand,  tensile  strength,  and  name  of 
IRON  PLATES,    maker,  plainly  stamped  on  each  plate.    Tensile  strength 
to  be  not  less  than  50,000  Ibs.  per  square  inch  of  section, 

with  a  good  percentage  of  ductility.    Heads  to  be of 

an  inch  thick,  of  the  best  C.  H.  No.  1  Flange  iron. 
FOR  STEEL. 

j 

STEEL    PLATES.  |  Shell  plates  to  be of  an  inch  thick,  of  homogeneous 

steel  of  uniform  quality,  having  a  tensile  strength  of  not 
less  than  60,000  Ibs.  per  square  inch  of  section,  nor  more 
than  65,000  Ibs,  with  45  per  cent,  ductility,  as  indicated 
by  the  contraction  of  area  at  point  of  fracture  under 
test.  Name  of  maker,  brand  and  tensile  strength  to  be 
plainly  stamped  on  each  plate.  Heads,  to  be  of  same 

quality  as  plates  of  shell  in  all  particulars, of  an  inch 

thick. 


FLANGES. 


KIVETING. 


BRACES. 


HOW     SET      AND 
FASTENED. 


All  flanges  to  be  turned  in  a  neat  manner  to  an  internal 
radius  of  not  less  than  two  inches  (2"),  and  to  be  clear  of 
cracks,  checks,  or  flaws. 

Boiler  to  be  riveted  f-inch  rivets  throughout.  All 
girth  seams  to  be  single  riveted.  All  horizontal  seams 
to  be  double  staggered  riveted.  Rivet  holes  to  be 
punched  or  drilled  so  as  to  come  fair  in  construction. 
No  drift-pin  to  be  used  in  construction  of  boiler. 

There  are- to  be  twenty  (20)  braces  in boiler  — ten 

(10)  on  each  head,  none  of  which  are  to  be  less  than 
three  (3)  ft.  long.  Braces  to  be  made  of  best  round  iron, 
of  one  (1)  inch  in  diameter,  and  of  single  lengths. 
There  are  to  be  seven  (7)  lengths  of  T  iron,  four  (4) 
inches  broad  and  one-half  (J)  inch  thick,  four  (4)  being 
eight  (8)  inches  long,  two  (2)  being  sixteen  (16)  inches 
long,  and  one  (1)  eighteen  (18)  inches  long,  placed  radi- 
ally; and  riveted  with  f-inch  rivets  to  each  head,  as 
shown  in  drawing.  The  holes  for  fastening  the  braces 
to  these  radial  brace-bars  are  all  to  be  drilled.  The 
braces  are  to  be  fastened  with  suitable  jaws  and  turned 
pins  or  bolts,  so  as  to  realize  strength  equal  to  inch 
round  iron.  Braces  to  be  set  as  shown  in  drawing,  and 
to  bear  uniform  tension. 


EXTERN  A  LL  Y  FIRED  STA  T10NA  R  Y  BOILERS. 


71 


MAN-HOLES.  Boiler to  have  one  man-hole,  eleven  (11)  inches  by  fif- 
teen (15)  inches,  with  strong  internal  frame  (as  shown  in 
drawing),  and  suitable  plate,  yoke,  and  bolt,  the  propor- 
tions of  the  whole  such  as  will  make  it  as  strong  as  any 
other  section  of  the  shell  of  like  area. 

HAND-HOLES.       Boiler to  have  two  hand-holes,  with  suitable  plates 

yokes,  and  bolts,  located  one  in  each  head  below  the 
tubes,  as  shown  in  the  drawing. 

NOZZLES.  Boiler to  have  two  cast-iron  nozzles,  four  (4)  inches 

internal  diameter,  one  for  steam  and  the  other  for  safety  - 
I  valve  connections,  securely  riveted  to  boiler. 

WALL -PLATES.      Boiler to  have  four  cast-iron  lugs,  two  on  each 

side,  the  rear  lugs  each  to  rest  on  three  transverse  rollers, 
one  inch  in  diameter,  which  are  to  rest  on  suitable  cast- 
iron  wall-plates,  as  shown  in  drawing,  front  lugs  to  rest 

BLOW-OUT.  on  suitable  wall-plates,  without  rollers.    For  blow-out 

connection,  one  plate,  J-inch  thick,  to  be  secured  with 
rivets  driven  flush  in  inside  of  the  shell,  and  tapped  to 
receive  a  two  (2)  inch  blow-pipe. 

FRONT.  Boiler to  be  provided  with  cast-iron  front  and  all 

the  requisite  doors  and  fastenings  for  facility  of  access 
to  tubes,  furnace,  and  ash-pit. 

BUCKSTAVES.        Boiler to  be  provided  with buckstaves;  also 

all  bolts,  rods,  nuts  and  washers,  anchor-bolts  to  extend 

GBATE  BARS.  in  setting  beyond  bridge-wall;  also  bearer  and  grate  bars 
(pattern  to  be  selected);  also  cast-iron  door,  to  be  at  least 
two  (2)  feet  by  three  (3)  feet  and  provided  with  liner 

plate,  for  back  tube  door— and door  fifteen  inches 

by  fifteen  inches  for  flue  for  side  or  rear  end. 

FITTINGS.  Boiler to  be  provided  with  one  safety-valve, 

inches  in  diameter, inch  steam  gauge  of  standard 

make,  three  gauge  cocks  properly  located,  also  one  glass 
water  gauge,  a  2-inch  open  way  blow-valve,  and  feed  and 
check  valves,  each  one  and  one- quarter  inch. 

FUSIBLE   PLUG.    Boiler to  be  provided  with  a  fusible  plug  so  located 

that  its  centre  shall  be  two  inches  above  upper  row  of 
tubes  at  back  end. 

DAMPER.  |  Boiler to  be  provided  with  a  damper  with  suitable 

hand  attachments,  easily  accessible  at  the  front  of  the 
boiler,  damper  to  be  fitted  to  the  throat  of  the  smoke  - 
arch,  as  near  as  practicable  to  the  tube  openings,  and  of 
area  equal  to  the  cross  section  of  all  the  tubes. 
The  size  and  description  of  parts  to  conform  substan- 
tially to  the  details  of  the  accompanying  plan.  All  the 
above  to  be  delivered  at 


STEAM  MAKING;  OR,  BOILER  PRACTICE. 

and  all  the  material  and  workmanship  to  be  subjected  to 
the  inspection  of  and  approved  by  the  Hartford  Steam 
Boiler  Inspection  and  Insurance  Company. 

The  axes  of  the  cylinders  are  sometimes  placed  vertically  as  well  as  in- 
clined. Of  the  water  tube  type  we  will  only  mention  one  in  which  a  number 
of  cone-shaped  tubes  hang  from  a  horizontal  drum  into  the  fire,  and 
Cadiats  in  which  three  horizontal  drums  are  connected  to  a  fourth  above 
them  as  a  steam  drum,  and  from  the  former  vertical  cylinders  of  ten  or 
twelve  inches  hang;  those  from  the  inner  drum  are  connected  at  the  bot- 
tom by  a  horizontal  drum  over  the  furnace,  while  those  from  the  side 
drums  are  carried  below  the  level  of  the  grate,  and  each  has  hand  hole  and 
plate  accessible  from  below.  This  boiler  seems  to  combine  many  good 
features. 

A  form  of  upright  fire  tube  externally  fired  boiler,  introduced  by  Mr. 
George  H.  Corliss,  of  Providence,  is  shown  by  an  example  taken  from  the 
Pawtucket  Water  Works,  at  Pawtucket,  K.  I.  These  boilers  when  mod- 
erately worked  with  a  low  water  have  given  steam  in  a  superheated  state. 

There  are  three  boilers  at  the  Pawtucket  Water  Works,  each  four  feet 
in  diameter  and  fourteen  feet  high,  carried  on  two  cast-iron  man-head 
trunnions.  There  are  forty- eight  3-inch  tubes  arranged  with  a  central 
gangway  and  a  mud  pan  stayed  to  the  bottom  by  stay  bolts  and  tied  to  the 
top  by  rods.  The  shell  is  partly  exposed  to  the  fire  and  the  circulation  is 
up  on  the  outside  and  down  the  middle,  thus  depositing  sediment  in  the 
"mud  pan."  The  steam  connections  are  made  by  a  casting  acting  as  stif- 
fener  for  the  upper  head.  The  water  line  may  be  varied  from  five  to  nine 
feet, — in  the  lower  places  about  20°  superheating  is  obtained. 


EXTERNALLY  FIRED  STA  TIONARY  B01L&RS. 


73 


Feet 
al  Metres 

CORLISS    BOILER   AT    THE    PAWTUCKET   WATER   WORKS, 
PAWTUCKET,    R.    I. 


CHAPTER     IV. 

INTERNALLY  FIRED  STATIONARY  BOILERS 

As  but  very  few  horizontal  internally  fired  boilers  are  used  in  the 
United  States  for  stationary  purposes,  we  have  quoted  entire,  by  the  kind 
permission  of  the  author,  a  paper  by  Mr.  Lavington  E.  Fletcher,  Chief 
Engineer  of  the  Manchester  Steam  Users'  Association,  a  boiler  insurance 
company  in  England,  as  the  highest  authority  on  this  subject  in  the  world; 
and  the  paper  is  so  admirably  adapted  to  our  purpose  and  so  well  written 
that  we  preferred  to  leave  it  in  the  original,  fearing  that  it  might  be  in- 
jured if  incorporated  with  our  work  in  any  other  manner. 

The  examples  selected  are:  A  single-flued  internally  fired  boiler, — 
a  Cornish  boiler  exhibited  and  tested  at  the  Dusseldorf  Exhibition.  This 
boiler  was  constructed  with  the  corrugated  flue  introduced  by  Fox,  and 
therefore  differs  in  this  respect  from  the  older  forms  of  Cornish  boilers,  it 
is  therefore  adapted  for  much  higher  pressures  than  were  formerly 
carried.  The  setting  is  not  an  example  of  ordinary  practice,  which  is  of 
the  Lancashire  type. 

Double-flued  boilers— a  pair  exhibited  at  the  Vienna  Exhibition  of 
1873,  by  Messrs.  D.  Adamson  &  Co.,  the  introducers  of  the  flange  joint 
used  in  the  flues.  This  boiler  is  rather  shorter  than  that  recommended  by 
Mr.  Fletcher,  but  in  most  respects  conforms  to  his  suggestions. 

For  the  Galloway  type  we  illustrate  three  out  of  four  boilers  built  by 
the  Edgemoor  Iron  Company  for  the  Crystal  Plate  Glass  Company:  their 
works  are  situated  23  miles  south  of  St.  Louis.  These  boilers  were  put 
in  in  1880,  and  while  exposed  to  very  hard  work  have  given  every 
satisfaction.  The  specifications  under  which  they  were  built  are  ap- 
pended.* 

The  most  usual  type  of  internally  fired  stationary  boiler  in  the  United 
States,  is  the  locomotive,  this  being  used  by  most  of  the  railroad  companies 
in  their  machine  shops,  and  by  several  of  the  lately  constructed  water 
works,  such  as  at  Lawrence,  Mass.,  and  the  Calumet  and  Hecla  mines,  Mich. 
The  old-fashioned  "drop  return  flue"  or  "tubular"  boilers  introduced  by  Mr. 
Kirkwood  at  the  Brooklyn  Water  Works  and  copied  at  many  places,  are 
open  to  all  the  criticisms  of  Mr.  Fletcher's  paper,  as  being  weakened  by 
having  large  holes  cut  in  the  shell,  rendering  them  unfit  for  the  higher 
pressures  now  universal.  At  the  Buffalo  Water  Works  the  boilers  are  of  the 
North  River  type,  as  also  those  at  the  Cleveland  Water  Works — the  latter 
being  very  large. 

The  price  of  these  boilers  at  Edgemoor,  Delaware,  on  board  the  cars  was  $3,880  each. 


JNTERNALL Y  FIRED  STA TIONAR Y  BOILERS.  75 

The  example  selected  is  one  of  Mr.  Leavitts,  this  being  one  of  the  latest. 

The  vertical  boiler  with  internal  furnace  ^s  subject  to  almost  endless 
modification,  and  we  select  for  illustration  a  very  good  example  designed 
by  the  Hartford  Boiler  Inspection  and  Insurance  Company. 


ON  THE  LANCASHIRE  BOILER. 
ITS  CONSTRUCTION,  EQUIPMENT,  AND  SETTING. 

[A  paper  by  ME.  LAVINGTON  E.  FLETCHEE,  Chief  Engineer  of  the  Manchester  Steam 
Users'  Association,  read  before  the  Institution  of  Mechanical  Engineers,  London.] 

The  Lancashire  type  of  boiler  differs  only  from  the  Cornish  in  one 
point,  namely,  that  the  Lancashire  boiler  has  two  furnace  tubes,  whereas 
the  Cornish  has  but  one.  In  both  types  of  boilers  the  shell  is  cylindrical, 
the  ends  are  flat,  and  the  furnace  tubes  are  carried  through  from  front  to 
back,  below  the  ordinary  water  line,  while  the  boilers  are  laid  horizontally 
and  fired  internally.  Internal  firing  is  essential  either  to  a  Lancashire  or 
to  a  Cornish  boiler.  It  is  a  mistake  to  speak  of  an  internally  fired  Lan- 
cashire or  an  externally  fired  Cornish  boiler,  though  this  is  frequently 
done.  If  the  fires  are  taken  out  of  the  furnace  tubes  of  a  Lancashire 
boiler  and  put  underneath,  it  is  a  Lancashire  boiler  no  longer,  but  becomes 
an  externally  fired  double  flued  boiler,  and  if  a  Cornish  boiler  be  treated 
in  the  same  way  it  becomes  an  externally  fired  single  flued  boiler.  These 
boilers  owe  their  names  to  the  counties  in  which  they  were  first  brought 
into  general  use.  The  single  furnace  boiler  was  introduced  early  in  the 
present  century  by  Trevethick  in  Cornwall,  and  is  therefore  called  Cornish. 
The  double  furnace  boiler  was  introduced  in  1844,  by  Fairbairn  and  Heth- 
erington,  in  Manchester,  and  is  therefore  called  Lancashire. 

In  laying  down  Lancashire  boilers,  the  fact  has  been  too  frequently 
lost  sight  of,  that  directly  a  fire  is  lighted  within  them,  they  begin  to  move. 
The  flat  ends  to  breathe  outward,  the  furnace  tubes  as  well  ^s  the  shell  to 
hog  upwards,  and  the  whole  structure  to  elongate.  If  sufficient  allowance 
is  not  made  for  these  movements,  straining  and  sometimes  rupture  occurs; 
while  tendency  to  this  is  frequently  aggravated  by  putting  in  an  extra 
thickness  of  metal  with  a  view  of  adding  strength,  the  additional  thick- 
ness increasing  the  unequal  expansion  of  the  parts.  For  some  years  the 
writer  has  had  opportunities  of  observing  a  large  number  of  boilers  of  the 
Lancashire,  as  well  as  other,  types  in  work  under  the  inspection  of  the 
Manchester  Steam  Users'  Association,  and  from  these  observations  he  has 
endeavored  to  mature  as  complete  a  boiler,  in  construction,  equipment, 
and  setting,  as  possible.  In  doing  this  the  folio  wing  points  have  been  kept 
in  vie  w :  to  make  the  boiler  safe  for  a  working  pressure  of  from  75  pounds  to 
100  pounds  per  square  inch,  to  make  the  structure  elastic  so  that  it  may  not  be 
rent  by  the  movement  of  the  parts  consequent  on  alternate  expansion  and 
contraction,  but  may  be  able  to  endure  the  work  of  years;  and  to  set  the 


76  STEAM  MAKING;  OR,  BOILER  PRACTICE. 

boiler  and  arrange  the  fittings  so  that  the  whole  shall  be  above  board  and 
accessible  for  inspection.  The  writer  does  not  agree  with  the  view  too 
generally  held1,  but  most  obstructive  to  improvement,  namely,  that  any- 
thing will  do  for  a  boiler,  and  that  it  is  only  a  boiler  after  all.  He  thinks 
that  a  boiler  should  receive  as  much  attention  as  an  engine,  that  it  should 
be  made  with  as  much  accuracy  and  attended  with  as  much  care,  that  the 
fireman  should  not  be  condemned  to  work  in  a  dark  dirty  hole  called  a 
stoke  hole,  and  the  boiler  assumed  to  be  black  and  grimy,  but  that  the 
boiler  should  be  placed  in  a  suitable  house  kept  bright  and  cheery,  and 
the  fittings  as  well  as  the  whole  structure  kept  clean  and  in  first-rate  work- 
ing  order;  also  that  the  fireman  should  be  stimulated  to  become  as  profic- 
ient in  the  art  of  using  his  shovel  and  managing  the  fire,  as  a  fitter  in  using 
file  and  erecting  an  engine.  If  this  practice  happily  adopted  by  some  were 
to  become  general,  and  first-class  boilers  were  laid  down,  instead  of  low 
priced  ones,  the  scientific  boiler-maker  would  have  fairer  scope,  the  steam 
user  would  derive  economy,  and  the  public  would  be  benefited  by  the 
prevention  of  explosions  as  well  as  by  the  abatement  of  the  smoke  nuisance. 

The  Lancashire  boiler  has  many  variations  beside  the  simple  form  al- 
ready described.  There  is  the  Galloway  boiler,  in  which  the  furnaces 
instead  of  running  through  from  one  end  to  the  other,  unite  in  an  oval 
flue  strengthened  by  water  pipes.  There  is  the  multi- tubular,  in  which 
the  furnace  tubes  unite  in  a  combustion  chamber  from  which  a  number  of 
small  flue  tubes  about  three  inches  in  diameter  and  six  feet  long  run  to 
the  back  of  the  boiler.  There  is  Hills  multi-flued  boiler,  in  which  seven, 
flues  about  11  inches  in  diameter,  and  8  to  10  feet  long,  take  the  place  of 
the  small  tubes  in  the  multi-tubular  boiler.  There  are  also  others  in  which 
the  furnace  tubes  branch  off  to  the  sides  or  bottom  of  the  shell,  instead  of 
running  right  through  to  the  back  end.  To  all  these  variations  in  the 
Lancashire  boiler  and  also  to  the  Cornish,  this  paper  applies  as  to  the  con- 
struction of  the  shell  and  furnace  tubes,  as  well  as  inregard  to  the  equip- 
ment and  setting  of  the  whole. 

To  assist  in  the  construction  of  Lancashire  boilers  for  high  pressure, 
the  Manchester  Steam  Users'  Association  authorized  the  construction  of  a 
boiler  expressly  for  undergoing  a  series  of  hydraulic  bursting  tests,  and 
the  manufacture  of  the  boiler  was  entrusted  to  Mr.  Beeley,  of  Hyde  Junc- 
tion, who  has  heartily  seconded  the  views  of  the  Association  and  rendered 
valuable  assistance  in  the  prosecution  of  the  trials. 

This  experimental  boiler  is  seven  feet  diameter,  which  is  the  usual 
size  for  mill  service.  It  is  adapted  for  a  working  pressure  of  75  pounds 
per  square  inch  and  its  construction  is  as  subsequently  described:  a  num- 
ber of  experimental  bursting  tests  have  already  been  made,  careful  obser- 
vations being  taken  of  the  behavior  of  the  boiler  under  pressure.  These 
tests  have  already  furnished  valuable  information,  and  when  completed 
will  be  fully  reported.  Some  of  the  results  are  given  in  this  paper.  In 
order  to  preserve  the  precise  form  and  character  of  the  rents,  the  solid 
plating  around  them  has  been  cut  out  intact:  several  of  these  specimens 
are  exhibited  at  the  meeting.  An  actual  end  plate  of  a  boiler  seven  feet 


UNIVERSITY 


IN  TERN  ALL  Y  FIRED  8TA  TTONAR  Y  BOILSRS.  77 

in  diameter,  equipped  with  the  usual  fittings,  has  also  been  prepared  for 
exhibition,  this  boiler  front  has  been  made  by  Mr.  Clayton, 
who  was  one  of  the  earliest  to  assist  the  writer  in  gettingj^tTj^st-elaas 
boiler  equipment  for  the  Manchester  Steam  Users' 

CONSTRUCTION. 


Dimensions. — Short  boilers  are  found  to  do  more  work, 
than  long  ones.  This  has  been  confirmed  by  experiments  on  the  rap] 
of  evaporation  by  Mr.  Charles  Wye  Williams  and  others.  Also  short  boilers 
strain  less  than  long  ones  and  are,  therefore,  less  liable  to  need  repair.  A 
length  of  30  feet  should  be  the  maximum,  while  with  regard  to  the  mini- 
mum some  Lancashire  boilers  to  suit  particular  positions  have  been  made 
as  short  as  21  feet  and  found  to  work  well  though  the  fittings  become 
rather  crowded.  The  length  recommended  and  now  generally  adopted  is 
27  feet. 

The  diameter  of  the  boiler  is  governed  by  the  size  of  the  furnaces, 
which  should  not  be  less  than  2  feet  9  inches,  to  admit  of  a  suitable  thick- 
ness of  fire,  and  afford  convenience  in  stoking.  Thick  fires  are  more  eco- 
nomical than  thin  ones. 

The  space  between  the  two  furnace  tubes  should  not  be  less  than  5 
inches  and  that  between  the  furnace  tubes  and  side  of  the  shell  4=  inches 
in  order  to  afford  convenient  space  for  cleaning  and  for  the  free  circula- 
tion of  the  water  as  well  as  to  give  sufficient  width  of  end  plate  for  enabling 
it  to  yield  to  the  expansion  and  contraction  of  the  furnace  tubes.  With 
this  width  of  water  space  it  will  be  found  that  furnace  tubes  having  a 
diameter  of  2  feet  9  inches  require  a  shell  of  7  feet,  which  will  afford  a 
headway  of  about  2  feet  9  inches  from  the  crown  of  the  furnaces  to  the 
crown  of  the  shell.  A  furnace  3  feet  in  diameter  gives  room  for  a  better 
fire  than  one  2  feet  9  inches,  but  it  requires  a  shell  7  feet  6  inches  in  dia- 
meter. For  high  pressures  the  smaller  diameter  of  7  feet  is  generally 
preferred  and  has  come  to  be  adopted  as  a  standard  size  for  mill  boilers 
throughout  Lancashire,  though  one  of  7  feet  6  inches  makes  a  good  boiler 
and  gives  a  greater  horse -power  per  foot  of  frontage  than  one  of  7  feet  dia- 
meter. The  diameters,  both  of  the  shell  and  of  the  furnace  tubes,  are 
measured  internally,  that  of  the  shell  being  taken  at  the  inner  ring  of  the 
plating. 

Ends.— The  ends,  more  especially  ths  front,  are  the  seat  of  the  groov- 
ing action  which  occurs  in  Lancashire  boilers  when  disproportioned. 
These  grooves  occur  inside  the  boiler  and  around  the  furnace  mouth. 
They  are  the  product  of  mechanical  and  chemical  action  combined.  The 
plate  is  fretted  by  being  worked  backwards  and  forwards  by  the  movement 
of  the  furnace  tubes,  consequent  on  the  action  of  the  fire,  and  when  in 
that  condition  is  attacked  by  the  acidity  of  the  water.  To  prevent  this 
grooving  the  ends  should  be  rendered  elastic  so  as  to  endure  the  buckling 
action  without  fatigue.  To  secure  this  elasticity  there  should  be  not  only  a 


78  STEAM  MAKING;  OR,  BOILER  PRACTICE. 

sufficient  -width  of  end  plate  between  the  two  furnace  tubes  as  well  as  be- 
tween them  and  the  shell  as  already  explained,  but  also  a  space  of  9  inches 
between  the  centre  of  the  bottom  rivet  in  the  gussets  and  those  at  the  fur- 
nace mouth. 

Also  five  gusset  stays  are  found  to  work  better  than  any  other  number. 
With  five  gussets  one  falls  on  the  centre  line,  which  is  not  only  the  weakest 
part  of  the  front  end  plate,  and  thus  where  it  requires  the  most  support, 
but  also  where  it  can  be  held  fast  without  resisting  the  movements  of  the 
furnace  tubes.  The  part  of  the  end  plate  that  should  be  left  free  is  imme- 
diately over  the  furnace  crowns.  With  four  gussets  the  end  plate  is  more 
unguarded  at  the  centre,  which  is  the  weakest  part,  and  more  bound  im- 
mediately over  the  furnace  tubes,  which  is  the  line  of  motion. 

The  thickness  of  the  end  plates  is  sometimes  as  much  as  f -inch  for 
pressures  of  60  pounds  per  square  inch.  This  thickness,  however,  is  quite 
unnecessary,  and  only  tends,  by  its  rigidity,  to  cramp  the  furnace  tubes 
and  strain  the  parts.  Half  an  inch  has  been  repeatedly  and  successfully 
adopted  in  boilers  for  pressures  of  75  pounds  per  square  inch  and  fe  of 
an  inch  when  that  pressure  has  been  exceeded.  These  thicknesses  have 
proved  amply  sufficient.  In  applying  the  hydraulic  tests  to  boilers  of  the 
construction  and  proportions  now  described  before  leaving  the  maker's 
yard,  it  is  the  practice  to  carry  the  pressures  up  to  about  150  pounds  per 
square  inch,  and  to  strain  fine  cords  across  the  flat  ends  to  act  as  straight 
edges  from  which  to  gauge  the  ends  at  twelve  points,  measurements  being 
taken  before  the  test,  during  the  test,  and  after  the  test.  It  is  found,  as  a 
rule,  that  the  plate  under  pressure  bulges  outward  at  the  centre  from  ^  of 
an  inch  to  J  of  an  inch,  and  on  the  removal  of  the  pressure  returns  to  its 
original  position  without  suffering  any  permanent  set.  In  the  experimen- 
tal hydraulic  bursting  tests  the  ends>  though  only  J-inch  thick,  have  stood 
a  pressure  of  275  pounds  per  square  inch  without  leakage  or  any  appear- 
ance of  distress,  but  on  the  pressure  being  raised  to  300  pounds  the  front 
end  plate  displayed  signs  of  weakness  in  the  vicinity  of  the  mud-hole 
beneath  the  furnace  tubes.  With  this  exception  the  greatest  bulging  was 
i-inch  at  the  front  and  ^  of  an  incl1  at  tne  back;  while  the  greatest  per- 
manent set  was  only  ^  of  an  inch. 

Longitudinal  stays  are  frequently  introduced  to  assist  the  end  plates. 
In  the  experimental  tests  the  longitudinal  stays  were  taken  out,  so  that  it 
is  clear  that  they  are  not  absolutely  necessary  where  the  gussets  are  sub- 
stantial. Should  it,  however,  be  thought  desirable  to  adopt  them,  either 
as  an  assistance  to  the  gussets  when  too  weak,  or  as  an  extra  precaution, 
they  will  be  found  easy  of  introduction.  They  are,  therefore,  shown  in  the 
diagrams,  and  it  will  be  observed  that  they  are  secured  at  each  end  with 
double  nuts,  one  inside  the  boiler  and  one  outside,  and  one  placed  as  much 
as  14  inches  above  the  level  of  the  furnace  crowns,  and  as  close  together  as 
convenience  will  allow.  When  placed  directly  over  the  furnace  crowns 
and  only  a  few  inches  above  them  they  confine  the  furnace  tubes  too 
strictly  and  straining  ensues.  A  single  stay  on  the  vertical  centre  line  of 


IN  TERN  A  LL  Y  FIRED  STA  TIONARY  BOILERS.  79 

the  front  end  plate  is  correct  in  principle,  but  two  are  more  convenient  in 
application. 

To  increase  the  elasticity  of  the  front  end  plate  it  is  attached  to  the 
shell  by  an  external  angle  iron  ring  rather  than  by  an  internal  one,  or  by 
flanging.  It  is  not  necessary  to  attach  the  end  plate  at  the  back  of  the 
boiler  with  an  external  angle  iron  ring,  and  when  this  has  been  done,  the 
angle  iron  has  been  found  to  be  injured  by  the  action  of  the  flame.  Both 
of  the  end  plates,  instead  of  being  made  in  two  pieces  rivetted  together  at 
the  joint,  are  welded  so  as  to  afford  a  flat  surface,  which  in  the  case  of  the 
front  plate  is  more  convenient  for  the  attachment  of  the  mountings.  Also 
both  of  them  are  turned  in  the  lathe  at  the  outer  edge  so  as  to  be  rendered 
perfectly  circular  and  are  bored  out  at  the  openings  for  the  furnace  tubes. 

Furnace  Tubes. — The  longitudinal  joints  of  the  furnace  tubes  are 
welded  when  the  plates  are  of  iron,  and  double-rivetted  when  of  steel,  each 
belt  of  plating  being  made  in  one  length  and  thus  having  but  one  longitu- 
dinal joint.  All  the  transverse  seams  of  rivets  are  strengthened  by 
Adamson's  flanged  joint  or  with  an  encircling  hoop,  either  of  Bowling 
iron,  T-iron,  or  other  approved  section.  One  of  the  evils  that  has  attended 
internally  fired  boilers  has  been  the  frequent  collapse  of  the  furnace  tubes, 
but  this  danger  is  completely  avoided  by  strengthening  the  tubes  as  just 
described,  whereby,  instead  of  being  weaker  than  the  shell  as  before,  they 
are  rendered  stronger. 

This  has  been  shown  by  the  experimental  bursting  tests,  in  which, 
while  the  shell  has  been  burst  repeatedly,  the  furnace  tubes  have  not 
suffered  at  all  nor  shown  any  movement  on  being  gauged.  In  some  cases 
Petrie's  pockets,  and  in  others  Galloway's  conical  water  pipes  are  intro- 
duced as  a  caution  against  collapse;  while  in  others  again  the  water  pipes 
are  made  parallel,  and  either  rivetted  or  welded  in  place  so  as  to  form  one 
piece  with  the  flue  tube.  In  all  cases,  however,  the  transverse  seams  of 
rivets  over  the  fire  should  be  strengthened  with  flanged  seams  or  encir- 
cling hoops,  and  it  is  considered  desirable  to  continue  this  mode  of  con- 
struction throughout  the  entire  length  of  the  boiler,  whether  water  pockets 
or  water  pipes  are  introduced  or  not.  The  thickness  of  plates  in  the  fur- 
nace is  sometimes  as  much  as  J  inch.  This  leads  to  violent  straining  and 
frequent  leakage  at  the  furnace  mouths  and  other  transverse  seams  of 
rivets.  Many  2  ft.  9  in.  furnace  tubes,  though  only  ^g-inch  thick  have 
stood  a  hydraulic  test  of  120  pounds  per  square  inch  without  movement 
and  have  worked  satisfactorily  for  years  at  a  steam  pressure  of  60  pounds. 
It  is  advisable,  however,  to  have  them  a  little  thicker  than  this,  in  order 
to  afford  a  margin  for  waste  through  corrosion,  and  also  when  the  flanged 
seam  is  adopted  in  order  to  allow  for  the  thinning  that  occurs  in  drawing 
the  metal  to  make  the  flange.  A  thickness  of  f  of  an  inch  is  sufficient  for  a 
working  pressure  of  75  pounds  per  square  inch,  ^|  for  a  pressure  of  80 
or  90  pounds,  and  /tf  for  100  pounds  per  square  inch. 

Stays  are  sometimes  introduced  for  tying  furnace  tubes  to  the  outer 
shells  in  order  to  support  them.  Such  stays  are,  however,  in  the  Lan- 
cashire boiler  unnecessary,  and  when  rigid,  are  decidedly  objectionable; 


80  STEAM  MAKING;  OR,  BOILER  PRACTICE. 

furnace  tubes  should  be  left  free  to  move.  As  soon  as  a  fire  is  lighted 
within  them,  the  top  of  the  tube  becomes  hotter  than  the  bottom  and 
elongates.  This  makes  the  tube  arch  upwards.  In  conducting  a  series  of 
trials  in  1867  and  1868  for  the  South  Lancashire  and  Cheshire  Coal  Asso- 
ciation on  the  evaporative  efficiency  of  their  coals,  and  also  on  the  compar- 
ative merits  of  different  boilers,  the  writer  had  three  gauge  rods  attached  to 
the  crown  of  the  furnace  tubes  of  two  Lancashire  boilers  and  carried  up  ver- 
tically through  the  external  shell  by  means  of  brass  stuffing  boxes,  so  that 
a  ready  opportunity  was  afforded  of  witnessing  the  rise  and  fall  of  the 
furnace  tubes,  while  as  the  gauge  rods  divided  the  tubes  in  equal  lengths 
a  comparison  could  be  drawn  as  to  the  movements  of  the  different  parts. 

Constant  observation  showed  that  the  distortion  of  the  tubes  varied 
very  much  at  different  times,  being  most  severe  shortly  after  lighting  the 
fires,  while  the  colder  the  water  to  start  with  the  greater  was  the  rise  of 
the  crown.  As  soon  as  the  water  became  generally  heated  the  gauge  rods 
retired  to  their  old  position,  and  the  distortion  of  the  furnace  tubes 
seldom  lasted  more  than  an  hour. 

The  boilers  were  28  feet  long,  the  furnace  tubes  of  steel,  ^  of  an  inch 
thick  in  one  case,  and  of  iron,  f  of  an  inch  thick  in  the  other.  Care  was 
taken  not  to  strain  the  boiler  by  severe  firing,  steam  being  got  up  with  the 
dampers  only  partially  open,  yet  the  furnace  tubes  rose  §  of  an  inch  when 
the  flame  passed  round  the  boiler  in  the  external  brickwork  flues  in  the 
ordinary  way,  and  \  inch  when  they  passed  off  direct  to  the  chimney 
without  heating  the  outer  shell.  The  curve  that  the  flue  appears  to  assume 
is  not  a  segment  of  a  circle;  the  gauge  rod  at  a  quarter  of  the  length  of 
the  boiler  from  the  front  showed  in  one  case  as  high  a  rise  as  the  rod 
placed  midway  in  the  length  of  the  boiler,  and  in  another  case  £$  of  an 
inch  more.  This  is  just  what  might  be  expected  from  the  local  action  of 
the  fire  and  accounts  for  the  grooving  action  being  far  more  severe  at  the 
front  end  of  a  boiler  than  at  the  back,  and  shows  the  importance  of  afford- 
ing greater  elasticity  at  that  part.  Furnace  tubes  lashed  to  the  shell  often 
tear  themselves  away  from  it  in  ordinary  work,  and  the  fractured  stays 
rubbing  against  the  shell  leaves  a  witness  of  its  movements,  the  amount  of 
which  frequently  exceeds  that  just  mentioned.  In  one  case  a  furnace  tube 
that  had  a  stay  tying  it  to  the  top  of  the  shell  was  found  to  have  crumpled 
up  the  stay  and  broken  it  by  aii  upward  thrust,  showing  how  little  need 
there  had  been  for  tying  to  keep  the  furnace  tube  from  drooping. 

Shell. — The  shell,  which  is  ^  of  an  inch  thick  for  a  pressure  of  75  pounds 
per  square  inch,  and  T9g  of  an  inch  for  a  pressure  of  100  pounds,  is  com- 
posed of  plates  about  3  feet  wide,  which  are  laid  in  not  more  than  three 
lengths  round  the  circumference,  in  order  that  the  longitudinal  seams  may 
clear  the  brickwork  seatings.  The  longitudinal  seams  are  so  arranged  as 
to  break  joint,  and  avoid  the  centre  line  along  the  top  and  bottom  of  the 
boiler.  In  all  the  longitudinal  rents  obtained  under  the  experimental  hy- 
draulic tests  the  plates  bulged  outwards  at  the  middle  of  their  width,  and 
this  action  was  observed  to  a  slight  extent  before  rupture,  showing  that 
the  greatest  strain,  and  thus  the  point  of  first  fracture,  occurred  at  or  near 


INTERNAL!, Y  FIRED  8TA TIONARY  BOILMIS.  81 

the  centre  line  of  each  plate.  This  would  seem  to  show  that  breaking 
joint  is  of  practical  advantage,  and  that  a  boiler  composed  of  wide  plates 
is  not  so  strong  as  one  composed  of  narrow  ones. 

There  is  no  steam  dome.  Steam  domes  are  expensive,  weaken  the 
shell,  and  often  give  trouble  from  leakage  at  the  base  ;  added  to  this,  they 
are  inconvenient  in  carriage  as  well  as  in  revolving  a  boiler  on  its  seat,  as 
it  is  sometimes  desirable  to  do  for  repairs.  They  are  also  inconvenient  in 
covering  the  boiler  over,  and  in  the  great  majority  of  cases,  if  not  in  every 
instance,  they  are  perfectly  useless. 

To  prevent  priming  an  internal  perforated  pipe  is  adopted  in  place  of 
the  dome.  Under  hydraulic  pressure  a  steam  dome  3  feet  in  diameter  ^ 
of  an  inch  thick,  and  the  whole  of  the  shell  plate  at  its  base  cut  away,  so 
as  to  form  an  opening  as  large  as  itself,  the  flange  at  the  base  of  the  dome 
ripped,  at  a  pressure  of  150  pounds  per  square  inch. 

At  a  second  trial,  with  a  dome  of  the  same  diameter,  and  a  portion 
only  of  the  shell  plate  cut  away,  the  dome  strained  so  much  round  its  base 
and  caused  such  violent  leakage  that  a  pressure  of  more  than  235  pounds 
could  not  be  obtained.  At  a  third  trial,  the  steam  dome  having  been 
removed  and  reflxed  with  stouter  rivet  heads,  so  as  to  resist  the  upward 
strain  that  was  induced,  the  flange  on  the  bottom  of  the  dome  ripped  on 
the  centre  line  of  the  boiler,  at  a  pressure  of  260  pounds  per  square  inch. 
In  this  instance  the  workmanship  was  all  good  and  sound;  but  in  some 
cases,  where  domes  are  attached  with  inferior  reedy  angle  irons,  the  weak- 
ening effects  of  the  domes  must  be  much  greater.  Steam  domes  clearly 
establish  a  weak  point  in  a  shell,  and  are  better  avoided. 

The  manhole  is  guarded  with  a  substantial,  raised  mouthpiece  of 
wrought  iron,  welded  into  one  piece,  flanged  at  the  bottom  and  attached 
to  the  boiler  with  a  double  row  of  rivets,  the  thickness  of  the  upper  flange 
being  £  of  an  inch,  and  of  the  body  f  of  an  inch.  This  has  been  found  to 
stand  a  test  of  300  pounds  per  square  inch  without  the  slightest  indication 
of  straining.  A  raised  wrought  iron  manhole  mouthpiece  is  exhibited.  It 
is  too  frequently  the  practice  not  to  strengthen  manholes  with  any  mouth- 
piece at  all.  Many  explosions  have  arisen  from  this  cause,  rents  starting  in 
the  first  place  from  the  unguarded  manhole,  and  then  extending  all  over 
the  boiler.  The  loss  of  strength  is  owing  not  simply  to  the  amount  of 
metal  cut  away  by  the  opening,  but  also  to  the  action  of  the  cover,  which 
in  unguarded  manholes  is  internal.  This  internal  cover  bears  on  a  narrow 
edge  of  plating  all  round,  and  is  driven  outward  by  the  pressure  of  the 
steam,  and  also  pulled  in  the  same  direction  by  the  bolts  in  tightening  the 
joint.  In  fact  the  cover  acts  as  a  sort  of  mandrel,  which,  being  forcibly 
driven  through  the  manhole,  splits  the  boiler  open.  A  heavy  hydraulic 
test  shows  this  action  of  the  cover  by  curling  the  boiler  plate  up  around 
the  manhole.  Added  to  this,  the  joint  is  apt  to  leak,  and  thus  to  induce 
corrosion  and  thin  the  plate,  which  not  only  reduces  its  strength,  but 
leads  to  extra  force  being  applied  to  tighten  the  joint— several  explosions 
have  occurred  after  the  joint  has  been  re -made.  It  has  been  the  general 
practice,  until  recently,  to  make  the  raised  mouthpieces  of  cast  iron.  This, 


STEAM  MAKING;   OR,  BOILER  PRACTICE. 

however,  is  not  wise  for  the  high  pressures  now  in  use.  A  raised  manhole 
mouthpiece  having  a  clear  opening  of  16  inches,  which  is  the  usual  size, 
involves  a  hole  in  the  shell  plate  of  about  20  inches  in  diameter.  The  plate 
in  which  this  hole  is  cut,  unless  it  be  duly  strengthened,  becomes  the 
weakest  part  of  the  boiler  when  the  longitudinal  seams  are  double  rivet- 
ed, the  furnace  tubes  suitably  strengthened  with  encircling  rings,  and  the 
ends  well  stayed,  so  that  the  stability  of  the  entire  structure  depends  upon 
the  mouthpiece  ;  if  that  fails  the  whole  structure  fails.  Under  these  cir- 
cumstances it  is  evidently  unwise  to  risk  the  safety  of  the  boiler  on  a  piece 
of  cast  iron.  This  view  is  confirmed  by  the  behavior  of  cast  iron  manhole 
mouthpieces  under  hydraulic  pressure.  Several  have  failed  under  the  or- 
dinary test  at  the  boiler-maker's  yard,  while  at  one  of  the  experimental 
bursting  tests  a  cast  iron  manhole  mouthpiece,  of  substantial  pattern, 
measuring  Ig  inch  thick  in  the  lower  flange,  and  1  inch  in  the  body, 
rent  at  a  pressure  of  200  pounds  per  square  inch,  though  the  metal  exhib- 
ited a  good,  sound  fracture.  This  specimen  is  exhibited  to  the  meeting. 
It  would  appear  that  under  pressure  there  is  considerable  upward 
strain  on  the  plates  around  the  mouthpiece,  and  that  while  wrought  iron 
mouthpieces  are  able  to  accommodate  themselves  to  this  without  distress, 
cast  iron  ones  are  not.  These  tests  have  shown  that  wrought  iron  manhole 
mouthpieces  are  much  superior  to  cast-iron,  and  that  the  sooner  cast-iron 
ones  are  superseded  by  wrought-iron  ones  the  better. 

The  mud-hole  at  the  front  of  the  boiler  beneath  the  furnace  tubes  is 
also  fitted  with  a  substantial  mouthpiece.  This,  in  some  cases  is  external 
like  the  manhole  mouthpiece,  and  in  others  internal;  the  internal  ones 
have  the  advantage  of  being  less  in  the  way.  In  either  case  the  surfaces  at 
the  joint  between  the  body  of  the  mouth-piece  and  the  cover  are  faced 
true  so  that  the  parts  may  be  brought  together,  metal  to  metal. 

The  safety  valve  and  steam  stop  valve  are  sometimes  grouped  upon 
the  man-hole  mouthpiece  instead  of  being  fixed  direct  to  the  shell.  This 
is  done  in  order  to  reduce  the  number  of  openings,  on  the  principle  that 
the  fewer  holes  made  in  the  boiler  the  better.  This  argument  is  plausible 
but  fallacious;  the  man-hole  makes  the  largest  opening  and  therefore 
exerts  the  greatest  weakening  effect.  The  weakest  link  in  a  chain  is  the 
measure  of  strength  of  the  whole,  so  that  fixing  the  steam  stop  valve  and 
safety  valve  directly  to  a  boiler  with  suitable  fitting  blocks  does  not 
weaken  it.  Moreover  for  convenience  in  attaching  the  fittings,  these 
group  man-hole  mouthpieces  are  made  of  cast-iron,  which,  as  already  ex- 
plained, is  objectionable.  It  is  therefore  recommended  that  man -hole 
mouthpieces  should  not  be  complicated  by  the  addition  of  the  safety 
valves  or  other  fittings,  but  that  each  should  be  fixed  direct  to  the  shell 
independently  of  the  others. 

Blocks  for  the  Attachment  of  Fittings. — In  old  fashioned  practice  the 
fittings  were  bolted  directly  to  the  cylindrical  portion  of  the  shell.  This 
led  to  the  wasting  of  the  shell  through  leakage  at  the  joints,  so  that  it  has 
long  since  been  the  practice  to  rivet  short  stand  pipes  to  the  cylindrical 
portion  of  the  shell,  and  bolt  the  fittings  thereto,  the  joint  surface  between 


INTERNALL Y FIRED  STA T10NARY BOILERS.  83 

the  flanges  being  planed  up  true.  These  stand  pipes,  frequently  termed 
"fitting  blocks,"  are  not  only  more  convenient  for  the  attachment  of  the 
fittings,  but  also  being  rivetted  to  the  plate  and  made  of  substantial  sec- 
tion strengthen  the  plate  round  the  hole  cut  in  the  shell.  They  are,  as  a 
rule,  made  of  cast-iron,  but  it  becomes  a  question  whether  with  the  high 
pressures  now  in  use  they  should  not  be  made  of  wrought  iron.  At  one  of 
the  experimental  bursting  tests,  a  fitting  block  for  a  6-inch  steam  valve 
box  was  found  to  give  way  before  any  other  part  of  the  boiler  at  a  pressure 
of  275  pounds  per  square  inch,  though  the  flange  was  Ig -inches  thick,  the 
body  g  of  an  inch,  and  the  metal  sound. 

Seams  of  Rivets. — Those  running  longitudinally  in  the  cylindrical 
shell  are  all  double-rivetted  with  f-inch  rivets  spaced  about  2£  inches 
apart  longitudinally  and  2  inches  diagonally.  The  remaining  seams 
throughout  the  boiler  are  single-rivetted,  only  the  rivets  being  spaced  2 
inches  apart.  To  double  rivet  the  transverse  seams  adds  but  little  if  any 
strength  to  the  boiler,  though  it  increases  its  weight  and  cost.  It  would 
appear  that  the  strain  upon  the  transverse  seams  of  rivets  in  a  Lancashire 
boiler  is  over-estimated.  In  a  plain  cylindrical  boiler  without  furnace 
tubes,  the  strain  on  the  transverse  seams  of  rivets  is  precisely  half  that  on 
the  longitudinal  seams. 

By  the  introduction  of  the  furnace  tubes  not  only  is  the  longitudinal 
strength  increased  but  at  the  same  time  the  area  of  the  ends  upon  which 
the  steam  acts,  is  diminished  also.  So  that  in  the  Lancashire  boiler  the 
strain  on  the  transverse  seams  of  rivets  is  less  than  half  that  on  the  longi- 
tudinal seams.  The  force  of  this  reasoning,  however,  is  sometimes  dis- 
puted and  tie  rods  are  introduced  to  support  the  transverse  seams  of  rivets 
in  the  shell.  But  in  the  hydraulic  bursting  tests  with  the  tie  rods  removed, 
the  longitudinal  seams  of  rivets  were  found  to  fail  in  every  case  before  the 
transverse  seams  which  never  showed  the  slightest  signs  of  distress  and 
scarcely  leaked  a  single  drop,  while  some  of  the  longitudinal  seams  under 
severe  pressure  leaked  profusely. 

The  riveting  is  done  by  machine  in  preference  to  hand  in  the  cylin- 
drical shell,  in  the  furnace  tubes  and  as  far  as  practicable  in  the  flat  ends. 
In  the  experimental  bursting  tests  the  machine  work  proved  much  tighter 
than  the  hand  work.  The  rivet  holes  in  the  angle  irons,  T-irons,  and 
flanged  seams  are  drilled ;  those  in  the  plates  are  punched  by  most  makers, 
though  by  some  the  holes  are  drilled  throughout,  and  the  practice  of  drill- 
ing is  strongly  advocated  by  them.  In  investigating  an  explosion  that  oc- 
curred at  Blackburn,  in  1874,  the  mean  tensile  strength  in  twelve  tests  of  a 
solid  plate  was  found  to  be  21.19  tons  per  square  inch,  and  in  four  tests  of 
a  punched  plate  20.17  tons,  showing  a  loss  by  punching  of  1.02  tons  per 
square  inch,  or  about  5  per  cent.  The  question  of  drilling  versus  punch- 
ing, and  also  of  the  pitch  and  diameter  of  rivets,  is  one  that  deserves  fur- 
ther consideration,  and  it  may  be  added  that  a  boiler  7  feet  in  diameter, 
and  made  of  plates  /g  inch  in  thickness,  having  the  longitudinal  seams 
double  riveted  with  f-inch  rivets  spaced  3  inches  apart  longitudinally,  in- 
stead of  2|  inches  as  usual,  was  found  tight  at  a  hydraulic  pressure  of  120 


84  STEAM  MAKING;    OR,  BOILER  PRACTICE. 

pounds  per  square  inch.  The  edges  of  the  plates  at  the  longitudinal 
seams  of  rivets  are  planed  and  caulked  tightly  inside  as  well  as  out,  though 
in  many  cases  caulking  is  superseded  by  fullering. 

Material. — As  a  rule  boilers  made  under  the  inspection  of  the  Manches- 
ter Steam  Users  Association,  are  of  iron  in  the  shell,  while  steel  plates  are 
very  frequently  introduced  in  the  furnace  tubes  for  a  length  of  9  feet  over 
the  fire,  and  sometimes  from  one  end  of  the  boiler  to  the  other.  For  the 
furnace  tubes  steel  plates  have  been  found  to  give  great  satisfaction,  but  a 
little  suspicion  has  been  entertained  with  regard  to  their  use  for  shells, 
seeing  that  the  plates  are  then  in  extension,  and  that  a  small  flaw  through 
brittleness  might  extend  till  it  produced  serious  consequences.  "Best  best" 
plates  from  first-class  makers  are  always  recommended,  more  importance 
being  attached  to  ductility  than  to  their  tensile  strength.  Brands,  how- 
ever, are  uncertain,  and  it  is  thought  desirable  that  a  complete  system  of 
testing  should  be  adopted,  and  that  before  a  boiler  is  made  one  plate  out 
of  the  set  proposed  to  be  used  should  be  tested  as  a  check,  the  investi- 
gation having  special  reference  to  ductility.  Lowmoor  rivets  are  recom- 
mended and  are  frequently  used. 

EQUIPMENT. 

Fittings. — The  fittings  are  so  arranged  that  all  those  requiring  frequent 
access  are  immediately  within  reach  of  the  attendant  when  standing  in 
front  of  the  boiler.  The  feed  is  introduced  on  one  side  of  the  front  end 
plate  about  4  inches  above  the  level  of  the  furnace  crowns,  an  internal  dis- 
persing pipe  being  carried  along  inside  the  boiler  for  a  length  of  about  12 
feet,  and  perforated  for  the  last  4  feet  of  its  length.  On  the  opposite  side 
of  the  front  end  plate  is  fixed  the  scum  tap,  to  which  is  connected  a  series 
of  sediment  catching  troughs  fixed  inside  the  boiler.  In  the  centre  of  the 
end  plate  are  two  glass  water  gauges,  one  acting  as  a  check  upon  the 
other,  a  pointer  being  fixed  to  show  the  correct  height  at  which  the  water 
should  be  kept.  Immediately  above  the  water  gauges  is  a  dial  pressure 
gauge,  and  above  that  a  dead  weight  safety  valve.  Thus,  whenever  the 
attendant  opens  the  furnace  doors  to  charge  the  fires  he  has  the  height  of 
the  water  and  the  pressure  of  the  steam  directly  before  him.  Under  his 
feet  is  the  blow-out  tap  and  behind  him  the  coal  supply,  so  that  every- 
thing is  ready  to  hand.  He  has  not  to  climb  a  ladder  to  reach  the  water 
gauges  or  ascertain  the  steam  pressure,  nor  to  mount  on  the  top  of  the 
boiler  in  order  to  regulate  the  feed  supply.  A  handle  for  regulating  the 
damper  is  frequently  brought  to  the  boiler  front.  On  the  top  of  the 
boiler  are  two  safety  valves,  one  a  dead  weight  valve  of  external  pendulous 
construction,  the  other  a  low  water  valve.  But  convenience  of  manipula- 
tion is  not  the  only  reason  for  this  arrangement  of  fittings,  and  if  the  feed 
be  cold  and  be  introduced  near  the  bottom  of  the  boiler  it  is  apt  to  induce 
local  contraction  and  thereby  strain  the  transverse  seams  of  rivets  near  the 
bottom  of  the  shell,  but  when  introduced  near  the  surface  of  the  water  and 


IN  TERN  A  LL  Y  FIRED  STA  TIONA  R  Y  BOILERS.  85 

passed  through  an  internal  perforated  pipe  it  becomes  dispersed  before 
falling  to  the  bottom.  Further,  although  non-return  valves  may  be  intro- 
duced they  will  sometimes  fail  and  allow  the  water  to  escape,  whereby  the 
furnace  crowns  become  bare  and  over-heated.  When  the  feed  inlet  is 
placed  above  the  level  of  the  furnace  crowns  it  will  be  seen  that  they  can- 
not be  drained  bare  by  the  non-return  valve,  but  when  placed  at  the  bottom 
of  the  boiler,  the  boiler  may  then  be  emptied  by  such  an  occurrence. 

All  the  joint  surfaces  are  planed  up  true  and  the  parts  brought  to- 
gether, metal  to  metal,  the  edges  of  the  flanges  are  turned  as  well  as  the  bolts . 
while  the  heads  of  the  nuts  are  shaped  and  the  whole  got  up  like  a  piece 
of  engine  work  as  shown  by  the  end  plate  and  fittings  exhibited. 

Safety  Valves.— The  dead  weight  valve  which  is  of  the  Cowlum  type  is 
extremely  simple  and  efficient.  The  centre  of  gravity  of  the  load  being 
below  the  seating,  renders  unnecessary  either  wing  or  fang  for  keep- 
ing the  valve  in  position,  and  it  has  therefore  no  frictional  surface  to  get 
tight  or  stick  fast.  These  valves  are  loaded  with  flat  annular  plates  or 
rings,  and  the  shell  is  cast  with  mouldings  around  it  at  the  bottom,  which 
present  the  same  appearance,  the  whole  being  so  adjusted  that  each 
moulding  as  well  as  each  annular  plate  represents  a  pressure  of  5  pounds 
per  square  inch  on  the  valve.  Large  numbers  of  these  valves  are  in  use, 
and  they  are  highly  approved.  The  diameter  generally  adopted  is  4  inches, 
which  requires  approximately  a  load  of  8  cwt.  for  a  blowing-off  pressure  of 
75  pounds,  and  11  cwt.  for  100  pounds  per  square  inch.  On  this  valve  the 
addition  of  two  or  three  bricks  produces  no  appreciable  effect,  whereas  at 
the  end  of  a  long  lever  the  result  would  be  different.  To  double  the  blowing- 
off  pressure  it  would  be  necessary  to  add  about  8  cwt.  to  the  load  for  75 
pounds,  and  11  cwt.  for  100  pounds.  Such  an  addition  there  would  be 
great  difficulty  in  attaching  to  the  valve,  and  if  it  were  done  it  would  be 
so  conspicuous  as  at  once  to  call  attention  to  the  fact.  The  great  weight 
required  to  load  this  valve  is  considered  therefore  to  be  a  safeguard,  and 
several  explosions  due  to  overloading  have  been  met  with  which  would 
have  been  prevented  by  its  use. 

The  low  water  safety  valve  shown  is  of  the  Hopkinson  type,  but  there 
are  also  the  Kay  and  the  Lloyd  low  water  valves,  which,  though  varying 
in  detail  are  similar  in  their  object.  Each  has  a  lever  inside  the  boiler  to 
which  is  attached  a  float  so  that  when  the  water  falls  below  the  desired 
level  the  float  falls  also,  and  thus  raises  the  valve  and  allows  the  steam  to 
blow  off,  thereby  not  only  giving  an  alarm  but  also  lowering  the  pressure. 
Hopkinson's  valve  is  a  compound  one,  having  one  valve  seated  on  another; 
the  central  portion  is  loaded  by  a  dead  weight  inside  the  boiler  and  oper- 
ated on  by  the  lever  in  the  event  of  low  water,  while  the  annular  portion 
is  loaded  by  an  external  lever  and  weight  and  lifts,  along  with  the  central 
portion  in  the  event  of  high  steam.  These  valves  therefore  blow  off  on  the 
occurrence  either  of  high  steam  or  low  water.  The  outer  valve  is  5  inches 
in  diameter,  and  the  inner  one  2&  inches.  The  freedom  of  the  steam  valve 
can  be  tested  by  placing  the  hand  on  the  lever  when  the  steam  is  up, 
while  the  freedom  of  the  low  water  apparatus  can  be  tested  by  opening 


86  STEAM  MAKING;  OR,  BOILER  PRACTICE. 

the  blow-out  tap  and  lowering  the  water  level  to  within  about  6  inches 
of  the  furnace  crowns.  To  overload  this  valve  without  increasing  the 
weight  outside  would  necessitate  getting  inside  the  boiler  and  wedging 
down  the  dead  weight.  Under  such  circumstances  the  application  of  the 
hand  to  the  external  lever,  when  steam  was  up,  would  at  once  show  that 
something  was  wrong,  and  even  if  this  were  not  detected  the  external 
dead  weight  valve  if  free  would  come  to  the  rescue  while  it  would  be  seen 
at  a  glance  if  this  were  overloaded.  It  is  sometimes  recommended  to  have 
safety  valves  under  lock  and  key,  but  it  is  preferred  by  the  writer  to  have 
them  thoroughly  open,  so  that  their  publicity  may  be  their  protection. 
While  it  is  fully  admitted  that  no  arrangement  of  safety  valves  can  be  con- 
structed which  cannot  be  tampered  with  by  skilled  malice,  it  is  thought 
that  the  combination  of  the  two  valves  just  described  forms  a  very  safe 
arrangement. 

Furnace  Mountings.— The  furnace  mouthpieces  are  of  wrought-iron, 
finished  off  with  a  neat  brass  beading  and  kept  within  the  circle  of  the 
rivets  so  as  to  leave  these  exposed  to  view.  The  fire  doors  are  fitted  with 
a  sliding  ventilating  grid  on  the  outside  and  a  perforated  box  baffle  plate 
on  the  inside,  the  aggregate  area  of  the  air  passages  being  about  50  square 
inches  for  arch  door  or  about  3  square  inches  per  square  foot  of  fire  grate. 
The  fire  grate  is  6  ft  long  with  three  bars  in  three  equal  lengths  about  f  - 
inch  thick  and  spaced  f  of  an  inch  apart  for  windage.  The  bearers  consist 
of  two  wrought-iron  bars  carried  on  wrought-iron  brackets  riveted  to  the 
sides  of  the  furnace  tubes.  The  standard  length  of  grate  is  6  feet,  but  a 
shorter  one  is  productive  of  economy,  though  the  concentration  of  the  fire 
is  more  trying  to  the  boiler  and  has  been  found,  where  the  feed  water  has 
not  been  good,  to  injure  the  furnace  plates  and  render  it  necessary  to 
lengthen  the  grates. 

Brickwork  and  Flues. — The  boiler  is  set  on  side  walls  and  rests  on  fire- 
brick setting  blocks,  presenting  a  bearing  surface  5  inches  wide.  The  side 
flues  are  6  inches  wide  at  the  top  carried  up  to  the  level  of  the  furnace 
crowns  or  a  few  inches  above  and  down  to  the  level  of  the  bottom  of  the 
shell.  The  bottom  flue  has  a  width  equal  to  the  radius  of  the  boiler  and  a 
depth  of  about  2  feet.  The  dimensions  admit  of  ample  room  for  inspec- 
tion. By  keeping  the  width  of  the  bottom  flue  equal  to  the  radius  of  the 
boiler  the  angle  that  the  bearing  surface  of  the  seating  blocks  makes  with 
the  horizon  is  30°  for  any  diameter  of  shell. 

The  fla.me  immediately  after  leaving  the  furnace  tubes  passes  under 
the  bottom  of  the  boiler  and  returns  to  the  chimney  along  the  side  flues. 
This  is  not  the  course  approved  by  Mr.  Pole  in  his  treatise  on  the  Cornish 
Pumping  Engine  published  in  "Tredgold  on  the  Steam  Engine,  "in  1844,  in 
which  the  setting  of  the  Cornish  boiler  is  spoken  of  as  follows: 

"The  heated  current  first  impinges  on  the  top  of  the  tube  over  which 
"the  highest  and  therefore  the  hottest  portion  of  the  water  is  lying,  it  then 
"passes  along  the  side  flues,  where  it  finds  the  surfaces  cooler  than  before, 
"and  last  of  all  it  traverses  under  the  bottom  of  the  boiler  where  the  cold- 
"est  water  will  always  be.  By  this  means  the  fire  current  as  it  gradually 


INTERN  ALL  Y  FIRED  STA  TIONARY  BOILERS.  87 

"cools,  is  likewise  gradually  brought  to  act  upon  cooler  water  and  thereby 
"the  best  opportunity  is  afforded  for  the  extraction  of  the  free  caloric  it 
"contains.  The  descending  motion  of  the  fire  current  as  it  cools  in  the 
"flues  of  the  Cornish  boiler  is  upon  statical  principles  much  more  natural 
"and  more  calculated  to  prevent  the  unnecessary  discharge  of  heat  into  the 
"chimney  than  the  ascending  principle  of  the  ordinary  boilers." 

Allowing  the  last  heat,  however,  to  travel  under  the  shell  does  not  pro- 
mote the  circulation  of  the  water,  or  at  all  events  but  slowly,  so  that  in 
getting  up  steam  the  top  of  the  boiler  becomes  hotter  than  the  bottom 
from  which  straining  ensues.  If  in  addition  to  this  the  feed  water  when 
cold  be  pumped  in  or  near  the  bottom  of  the  boiler  the  straining  at  the 
transverse  seams  of  rivets  is  intensified.  Possibly  the  Lancashire  boiler  is 
more  subject  to  straining  and  seam  rending  at  the  bottom  of  the  shell 
than  the  Cornish  as  there  is  a  greater  body  of  dead  water  lying  there  in 
the  Lancashire  boiler,  in  addition  to  which  the  rate  of  combustion  per 
square  foot  of  fire  grate  is  much  more  rapid  in  the  Lancashire  district  than 
that  generally  adopted  in  Cornwall.  In  consequence  of  seam  rents  oc- 
curring at  the  bottom  of  Lancashire  boilers  when  the  last  heat  is  carried 
underneath,  the  plan  of  passing  the  flame  under  the  bottom  immediately, 
on  leaving  the  furnace  tubes,  and  also  of  introducing  the  feed  water  near 
the  surface  has  become  the  general  practice. 

The  question  of  economy  is  met  by  the  use  of  feed  water  heaters  con- 
sisting of  a  number  of  water  pipes  placed  in  the  main  flue  between  the 
boiler  and  the  chimney  and  kept  free  from  soot  by  an  automatic  scraper. 
A  good  feed  water  heater  will  raise  the  temperature  of  the  water  to  about 
240°.  This  answers  two  good  purposes;  it  economizes  the  waste  heat  escap- 
ing to  the  chimney  and  thus  reduces  the  coal  consumption,  while  at  the 
same  time  it  prevents  local  cooling,  thereby  preventing  straining  and 
saving  repairs.  It  has  been  found  by  experiment  that  passing  the  flames 
from  the  furnace  tubes  around  the  outer  shell  instead  of  direct  to  the 
chimney  adds  but  little  to  the  yield  of  steam,  though  it  promotes  economy 
of  fuel,  at  the  same  time  that  it  keeps  the  boiler  at  a  more  equable  temper- 
ature throughout. 

The  flooring  or  hearth  plates  at  the  front  of  boiler  are  set  so  as  not  to 
butt  against  the  boiler,  which  is  too  often  the  case,  but  so  as  to  be  entirely 
below  it,  thus  leaving  the  whole  of  the  front  end  plate  open  to  view. 
Where  there  is  a  range  of  boilers  these  flooring  plates  extend  throughout 
the  width  of  the  boiler  house  and  being  finished  off  with  a  fender  flange 
where  abutting  against  the  boundary  walls  of  the  building,  as  well  as 
against  the  face  of  the  brickwork  setting,  they  present  a  very  neat  appear- 
ance. These  plates  are  carried  on  a  complete  system  of  framing  and  are 
arranged  for  easy  lifting.  The  hearth -pit  beneath  them  is  open  from  one 
side  of  the  boiler  house  to  the  other,  and  in  this  is  laid  the  main  feed  pipe 
as  well  as  the  discharge  pipe  from  the  blow-out  and  scum.  This  pit  is  about 
3  feet  wide  by  2J  feet  deep  so  as  to  afford  room  for  access:  the  flue  doors 
open  into  it.  The  face  of  the  brickwork  at  the  front  of  the  boiler  is  set 
back  6  inches  so  as  to  leave  the  angle  iron  with  its  circle  of  rivets  perfectly 


88  STEAM  MAKING;  Oft,  1101LEK  PRACTICE. 

open.  The  front  cross  wall  beneath  the  boiler  is  recessed  around  the 
blow-out  elbow  pipe  so  that  it  may  be  free  to  move  should  settlement  of 
the  boiler  take  place. 

Boiler  Covering  .—The  boiler  is  covered  with  an  arch  of  brickwork, 
leaving  a  space  of  about  2  inches  between  it  and  the  plates,  and  a  layer  of 
cork  shavings  or  a  coating  of  good  boiler  composition  or  other  suitable 
non-conducting  substance  is  introduced  into  this  space.  Openings  fin- 
ished off  with  bull-nosed  bricks  are  worked  round  the  fittings,  so  as  to 
leave  the  ring  of  rivets  by  which  they  are  attached  to  the  shell  exposed  to 
view.  Sometimes  the  boiler  is  covered  simply  with  a  layer  of  composition 
which  should  not  be  carried  over  the  flanges  of  the  fittings,  as  is  too  often 
the  case,  but  should  be  stopped  off  by  means  of  kerb  hoops  dropped 
around  the  flanges  and  a  kerb  cast-iron  nosing  to  guard  the  front  angle  iron. 

Connections. — All  connections  to  boilers  should  be  elastic  so  as  to  al- 
low of  their  movement.  If  the  main  steam  pipe  be  carried  across  the 
boilers  and  bolted  direct  to  the  junction  valve,  the  joints  are  strained  by 
the  raising  and  falling  of  the  boilers  as  they  are  set  to  work  and  laid  off. 
To  prevent  this  a  springing  length  should  be  introduced  between  the 
steam  stop  valve  and  main  steam  pipe.  Where  the  main  steam  pipe  has  a 
considerable  length  to  travel  to  the  engine,  it  should  not  be  taken  in  a  di- 
rect line,  but  should  be  carried  round  the  boiler  house  or  be  led  in  a  horse 
shoe  shaped  course  to  give  elasticity;  this  is  better  than  introducing  an 
expansion  joint  which  is  not  reliable.  Sometimes  expansion  diaphragms 
are  adopted,  but  these,  when  as  much  as  4  feet  in  diameter,  have  been 
known  to  lead  to  the  fractures  they  were  intended  to  prevent,  the  internal 
pressure  causing  them  to  bulge  outward  when  it  was  expected  they  would 
allow  the  pipes  to  expand  and  thrust  them  inwards.  A  case  of  this  sort  has 
recently  come  under  the  knowledge  of  the  writer  in  which  the  main  junc- 
tion valve  was  broken  off  by  the  thrust  occasioned  by  the  bulging  of  the 
expansion  diaphragm.  It  is  equally  important  that  the  feed  connection 
should  be  elastic,  and  from  the  want  of  elasticity  feed  valve  boxes  have 
been  known  to  fracture.  For  this  purpose  a  copper  elbow  connecting 
pipe  is  introduced  between  the  main  feed  pipe  and  the  stand  pipe;  in  some 
cases  a  wrought- iron  horseshoe- shaped  pipe  has  been  adopted  instead 
with  very  satisfactory  results. 

Connections  between  the  steam  stop  valves  and  main  steam  pipe  are 
frequently  made  to  incline  upwards,  so  that  the  water  may  drain  back  to 
the  boilers.  This  plan  is,  however,  objectionable,  for  when  one  of  the 
boilers  in  a  range  is  laid  off,  the  connecting  length  becomes  filled  with 
water  from  condensation  of  the  steam,  which,  cooling  by  radiation  sets  up 
a  violent  conflict  with  the  steam  whereby  the  pipes  are  sometimes  frac- 
tured. The  action  may  be  illustrated  by  the  commotion  which  occurs 
within  a  locomotive  tender  when  the  steam  from  the  boiler  is  turned  into 
it.  Further  than  this,  on  opening  the  steam  stop  valve  of  a  boiler  that  has 
been  laid  off  the  water  lying  on  the  top  of  the  valve  is  apt  to  be  carried 
forward  by  the  rush  of  the  steam  like  a  water  hammer,  and  sometimes  to 
burst  the  pipe.  To  prevent  this  the  steam  pipe  should  drain  towards  the 


INTERNA LL  Y  FIEED  STA  TIONAR  Y  BOIL&RS.  89 

engine  and  not  towards  the  boiler,  its  course  being  intercepted  by  a  sep- 
arator fixed  as  near  the  engine  as  convenient.  The  principle  on  which 
these  separators  act  is  that  of  making  the  steam  take  a  sharp  turn  to  shoot 
off  the  water  mixed  with  it  into  a  catch  chamber  prepared  for  the  purpose. 
Many  of  these  separators  are  now  at  work;  the  principle  was  advocated  by 
Dr.  Haycraft,  five  and  twenty  years  ago. 

Weight  and  Cost. — The  weight  and  cost  of  such  a  boiler  as  has  now 
been  described  is  about  12  tons  without  fittings;  with  fittings  15£  tons. 
The  cost  at  the  present  time  (1876)  delivered  on  the  premises  of  the  pur- 
chaser within  a  few  miles  of  Manchester  and  including  the  attachment  of 
the  fittings  is  about  £425.  The  plan  of  buying  a  boiler  at  so  much  per  ton 
and  then  the  fittings  at  so  much  extra,  is  quite  given  up  in  favor  of  pur- 
chasing the  whole  for  one  sum. 

Heating  Surface.—  Such  a  boiler  has  heating  surface  in  the  external 
shell  of  370  square  feet;  in  the  furnace  tubes,  without  water  pipes,  450  square 
feet,  in  the  water  pipes  30  square  feet,  making  a  total  of  850  square  feet. 
The  fire  grate  has  an  area  of  33  square  feet.  This  gives  for  every  square 
foot  of  fire  grate  26  square  feet  of  heating  surface.  The  surface  in  feed 
water  heaters  varies;  60  pipes,  each  affording  a  heating  surface  of  about  10 
square  feet  are  now  frequently  introduced  per  boiler,  making  a  total  heat- 
ing surface  of  600  square  feet,  or  about  three-fourths  of  that  in  the  boiler. 

Working  Results.— Such  a  boiler  as  that  described  will  burn  without 
distress  to  the  boiler  from  15  to  20  tons  of  coal  in  week  of  60  working 
hours,  or  from  17  pounds  to  23  pounds  per  square  foot  of  fire  grate  per 
hour.  This  may  be  done  without  making  smoke.  All  that  is  needed  is  to 
maintain  a  good  thickness  of  fire,  throw  on  the  coal  little  and  often,  admit 
a  little  air  above  the  bars  for  a  short  time  after  firing,  and  avoid  the  use  of 
the  rake.  The  coal  may  either  be  spread  over  the  whole  surface  of  the 
fire,  or  thrown  at  alternate  firing,  first  to  one  side  of  the  furnace  and  then 
to  the  other  on  the  "side  firing"  system  introduced  by  Mr.  Charles  Wye 
Williams. 

A  Lancashire  boiler  experimented  on  at  Wigan  with  furnaces  2  feet  7 
inches  in  diameter  and  a  fire  grate  4  feet  long  evaporated  83.54  cubic  feet 
of  water  per  hour  from  a  temperature  of  100°  at  the  rate  of  10.44  pounds  of 
water  per  pound  of  coal  when  burning  24  pounds  of  coal  per  square  foot 
of  fire  grate  per  hour.  With  a  fire  grate  6  feet  long,  it  evaporated  98.58 
cubic  feet  of  water  at  the  rate  of  10.37  pounds  of  water  per  pound  of  coal 
and  burnt  19  pounds  of  coal  per  square  foot  of  fire  grate  per  hour.  These 
results  were  obtained  at  atmospheric  pressure  with  the  help  of  a  water 
heater  with  good  round  coal  and  without  making  smoke.  The  boiler  des- 
cribed in  this  paper  having  furnaces  2  feet  9  inches  in  diameter  would 
evaporate  a  larger  quantity  of  water  per  hour.  Such  a  boiler  is  found  in 
practice  to  be  capable,  provided  the  steam  be  applied  to  a  fairly  econom- 
ical engine,  of  developing  200  indicated  horse -power  per  hour,  and  20  indi- 
cated horse-power  per  lineal  foot  of  boiler  frontage,  side  flues  included. 
A  Cornish  boiler  under  similar  conditions  is  capable  of  developing  16  in- 
dicated horse-power  per  lineal  foot  of  boiler  frontage.  This  leads  to  a 


90  STEAM  MAKING;  OR,  BOILER  PRACTICE. 

question  of  the  utmost  importance,  namely,  the  one  which  the  late  Mr. 
Robert  Stephenson  denned  as  the  "administration  of  the  steam"  and 
fuller  information  is  yet  needed  as  to  the  comparative  advantage  of  work- 
ing steam  on  the  compound  or  single  cylinder  principle,  also  as  to  the 
value  of  steam  jackets  as  well  as  with  regard  to  the  initial  and  terminal 
pressures  most  conducive  to  economy.  These  inquiries,  though  full  of  in- 
terest, cannot  be  entered  upon  in  the  present  paper,  but  one  of  the  essen- 
tials to  economy  is  the  power  of  raising  high  pressure  steam  steadily  and 
safely,  and  this  may  be  accomplished  by  the  use  of  the  Lancashire  boiler. 


The  example  taken  for  a  Cornish  boiler  is  one  exhibited  at  Dusseldorf 
in  1880,  and  subjected  to  the  competitive  trial  held  there.  It  is  7  feet  2^  in- 
ches in  diameter  and  31  feet  1  inch  long.  The  corrugated  flue  is  4  feet  3 
inches  in  diameter.  The  corrugations  are  probably  exaggerated  as  the 
usual  practice  is  6"xi£"  and  is  nearly  10  inches  from  the  shell.  The  set- 
ting is  peculiar  in  that  the  products  of  combustion  after  leaving  the  flue 
pass  under  the  boiler  and  then  return  on  the  sides  and  top,  thus  giving 
dry  steam.  The  pit  at  the  rear  end  is  to  hold  ashes  which  are  blown  by 
a  steam  jet  out  of  the  flue  while  in  steam.  The  usual  setting  for  the 
Cornish  boiler  is  similar  to  the  Lancashire. 

This  boiler  gave  the  best  results  as  to  evaporative  economy  of  all  tried 
at  Dusseldorf. 

The  proportions  of  this  boiler  are  as  follows: 

Orate  area  at  trial 15.8  sq.  ft. 

Grate  area  usual 24.5 

Heating  surface 841 . 5 

S  uperheating  surface 193 

Area  over  bridge 4.63     ' 

Area  through  flue... 13.00 

Area  through  side  flue 8 . 20     ' 

Area  through  damper  at  trial 4.4 

Ratio  heating  surface  to  grate 53.2 

Ratio  grate  to  air  space  in  grate 4.31 

Water  space 634  cu.  ft. 

Steam  space 259 

Weight  of  boiler 36736  Its. 

Brick  setting 1303  cu.ft. 

The  evaporation  reached  at  the  trial  was  10.854  pounds  of  steam  from 
1  pound  of  combustible  at  75  pounds  per  square  inch,  with  feed  at  130°  F. 
and  a  rate  of  3.85  pounds  of  water  per  square  foot  of  heating  surface  per 
hour.  The  side  flues  were  then  omitted  and  the  boiler  evaporated  5.92 
pounds  per  square  foot  of  flue  surface  and  gave  an  evaporation  of  8.17  per 
pound  of  combustible.  The  heating  surface  was  then  24.6  times  the  grate. 

The  same  makers  are  now  building  this  boiler  with  the  centre  of  the 
flue  not  in  the  same  vertical  plane  as  the  centre  of  the  boiler;  they  claim 
thereby  an  improved  performance  due  to  better  circulation  of  the  water. 

The  Lancashire  boilers  require  no  explanation  after  Mr.  Fletcher's 
paper. 

The  fire-box  boiler  at  the  mines  of  the  Calumet  and  Hecla  Mining  Co., 


INTERNAL!,  Y  FIRED  STA  T10NARY  BOILERS. 


92  STEAM  MAKING;  OR,  BOILER  PRACTICE. 

built  from  the  designs  of  Mr.  E.  D.  Leavitt,  is  probably  the  most  expen- 
sive stationary  boiler  made,  but  it  gives  a  very  high  economic  evapora- 
tion when  doing  a  good  deal  of  work,  and  for  steady  work,  night  and  day, 
is  probably  a  good  investment. 

The  shell,  fire-box  and  combustion  chamber  are  of  the  best  quality 
Siemens -Martin  steel,  which  possesses  an  ultimate  strength  of  about  65,- 
000  pounds,  an  elastic  strength  of  about  49,000  pounds,  an  extension  of 
22^0  per  cent,  with  a  reduction  of  area  at  fracture  of  58  per  cent.  The  me- 
tal is  therefore  of  excellent  quality.  The  stays  and  braces  of  the  "Best 
Ulster"  iron.  The  iron  rivets  are  "Burden's  Best."  The  rivet  holes  are 
punched.  The  tubes  are  iron  3£  inches  in  external  diameter,  and  4£  inches 
from  centre  to  centre,  and  18  feet  1  inch  long;  the  tube  sheets  are  i-inch 
thick.  The  inside  fire-box  sheets  and  the  combustion  chamber  are  f^- 
inch,  the  external  fire-box  ^,  and  the  shell  ^  of  an  inch  thick.  The 
shell  is  7  feet  in  internal  diameter,  and  is  butt- jointed,  with  straps  inside 
|  of  an  inch,  and  outside  of  ^  of  an  inch  in  thickness.  The  junction  of 
shell  and  fire-box  is  strengthened  by  inside  and  outside  sheet  on  the 
ring  of  throat  plates.  The  transverse  seams  are  double -ri vetted  to  the 
butt  straps  and  over  the  fire-box  the  sheets  are  lapped.  The  longitudinal 
seams  are  treble-rivetted  to  the  butt  straps,  the  outer  row  having  fewer 
rivets.  The  rivets  in  the  fire-box  are  f  of  an  inch,  in  the  shell  ^f  of  an 
inch.  The  stay  bolts  are  ^f  of  an  inch  in  diameter  and  are  spaced  4£  inches 
centres  horizontally  and  f  of  an  inch  vertically.  The  fire-box  is  double,  a 
water  leg  and  two  combustion  chambers  leading  into  a  single  chamber 
from  which  the  tubes  lead  to  a  smoke-box. 

Steam  is  taken  by  two  slotted  dry  pipes  through  an  8- inch  nozzle,  and 
two  5-inch  weight  and  lever  safety  valves  are  placed  on  a  second  8-inch 
nozzle.  A  man-head  on  a  nozzle  gives  access  above  the  tubec,  and  one  in 
the  smoke-box  below  the  tubes.  The  crown  of  the  furnace  and  combus- 
tion chambers  are  slung  by  stays  in  a  peculiar  manner,  adopted  to  give  ac- 
cess through  them  for  inspection;  the  heads  are  tied  by  light  tie  rods  1| 
inches  round  iron  with  swelled  ends,  and  held  by  nuts  and  washers.  Feed 
is  taken  through  the  top  of  the  shell  by  a  l^-inch  brass  pipe  led  through 
the  water  to  the  side  of  the  boiler. 

The  fire-box  rests  on  a  cast-iron  ashpit  and  the  shell  is  carried  on 
three  adjustable  cast-iron  stands  resting  on  balls.  Two  boilers  are  con- 
nected by  a  steam  drum  24  inches  in  diameter  and  about  16  feet  long, — the 
boilers  being  set  14  feet  centres. 

The  front  head  is  tied  to  the  first  sheet  of  the  shell  around  the  tubes 
by  short  bars,  and  the  upper  portion  of  both  front  and  back  head  is  stiff- 
ened with  angle  and  T-ii'on  bars. 

The  boiler  is  covered  with  a  coating  of  plaster  of  Paris  and  sawdust  2£ 
inches  thick,  covered  with  1  inch  of  the  best  hair  felt  and  a  painted  can- 
vass cover.  The  coal  used  is  an  inferior  quality  from  Ohio,  being  in 
evaporative  value  about  70  per  cent,  of  the  best  steam  coal.  It  is  intended 
to  use  an  artificial  draft  when  desired,  although  the  chimney  is  150  feet 
high,  and  by  this  means  to  burn  up  to  40  pounds  of  coal  to  the  square 


INTER*!  ALL  Y  FIRED  STA  TIONARY  BOIL  Bit  S. 


93 


94 


STEAM  MAKING;  OR,  BOILER  PRACTICE. 


96 


STEAM  MAKING;  OR,  BOILER  PRACTICE. 


foot  of  grate  per  hour.  The  evaporation  of  8.75  pounds  of  water  from  and 
at  212°  per  pound  of  inferior  coal  is  maintained  regularly,  and  a  similar 
pair  of  boilers  at  the  Lawrence  Water  Works  gave  12.46  evaporation  from 
Cumberland  bituminous  coal. 

SPECIFICATION 


For  Galloway  Boiler  (1876  Patent},  Edgemoor  Iron  Company.  To  Evaporate 
50  Cubic  Feet  of  Water  per  Hour.  For  Crystal  Plate  Glass  Company, 
Crystal  City,  Mo. 


SHELLS. 


FLUES, 


END-PLATES. 


The  shell  to  be  28  feet  long  by  7  feet  diameter,  and  to  be 
made  of  best  cold  blast  charcoal  flange-plates  ^-inch 
thick.  The  longitudinal  seams  to  be  double-rivetted  and 
to  be  crossed  one- half  the  length  of  the  plate  so  as  to 
avoid  a  continuous  line  of  rivets.  The  edges  of  all  the 
plates  to  be  planed  and  fullered,  not  caulked.  Front 
end  of  shell  to  be  provided  with  a  solid  welded  ring 
of  angle-iron  3  inches  by  3  inches  by  £-inch  for  attach- 
ment of  the  end. 

The  flues  to  consist  of  two  furnaces  each  2  feet  9£  inches 
in  diameter  formed  of  solid-welded  rings  of  best  cold 
blast  charcoal  fire-box  plates  f  of  an  inch  thick.  The 
transverse  seams  to  be  formed  by  flanging  the  plates  and 
inserting  a  solid  welded  ring  between  the  two  flanges. 
The  two  furnaces  to  unite  behind  the  fire  bridges  into  one 
flue  of  best  cold  blast  charcoal  flange  plates  made  in  accor- 
dance with  above-mentioned  patents.  The  flue  being 
hollowed  on  its  lower  side  to  give  more  room  for  clean- 
ing and  examination,  the  necessary  strength  being  ob- 
tained by  bringing  the  tubes  nearer  together  at  their 
lower  ends,  and  thus  avoiding  the  necessity  of  objec- 
tionably thick  plates  which  would  otherwise  be  required 
for  this  part.  This  flue  to  be  supported  by  means  of  33 
patent 'Galloway  Cone  Tubes  having  a  diameter  of  10£ 
inches  at  the  top  and  5|  inches  at  the  bottom,  the  whole 
of  these  tubes  to  be  interchangeable  and  to  have  all  their 
flanges  square  to  the  centre  line  of  the  tubes,  thus  put- 
ting less  strain  upon  the  iron  in  their  manufacture  and 
thereby  allowing  a  better  job  to  be  made. 
The  boiler  ends  each  to  be  made  in  one  piece  j%  of  an 
inch  thick,  of  the  best  cold  blast  charcoal  flange  iron. 
The  front  plate  to  be  securely  attached  tc  angle  iron  of 
shell  and  the  back  end  plate  to  be  flanged.  These  end 
plates  to  be  efficiently  stayed  by  means  of  suitable  gusset 
plates,  which  shall  be  fastened  by  double  angle-iron  to 


98 


STEAM  MAKING;  OR,  BOILER  PRACTICE. 


-3  lltf- 
-    54* 


SECTIONAL  ELEVATION. 


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OOOOO** 


UPRIGHT    BOILER, 

DESIGNED  BY  THE  HARTFORD  STEAM  BOILEE  INSPECTION  AND  INSURANCE  COMPANY, 

HARTFORD,  CONN.    10  FEET  LONG,  54  INCHES  DIAMETER.    HEATING 

SURFACE  :  SHELL,  4  SQUARE  FEET  ;  TUBES,  419  SQUARE 

FEET.     ESTIMATED  HORSE-POWER,  30^ 


100 


STEAM  MAKING;  OR,  BOILER  PRACTICE. 


MAN-HOLES. 


shell  of  boiler.  These  stays  shall  not  be  brought  down  too 
near  the  top  of  furnaces,  but  sufficient  space  shall  be  al- 
lowed for  expansion. 

One  wrought-iron  manhole  of  large  size  shall  be  fixed  on 
the  top  of  boiler,  and  one  of  smaller  size  fixed  on  the 
front  end  plate  below  the  flues,  both  to  be  rivetted  011 
and  to  be  faced  across  the  whole  surface  of  their  flanges; 
cast-iron  covers  for  the  same  to  be  provided  with  suit- 
able bolts. 

Before  leaving  the  works  the  boiler  shall  be  tested  with 
water  pressure  of  100  pounds  per  square  inch,  and  a  cer- 
tificate of  such  test  having  been  made  shall  be  furnished. 


TESTING. 


FURNACE  FIT- 
TINGS. 


FUSIBLE  PLUGS. 
BLOW-OFF  COCK 

FEED  VALVE. 

SAFETY  VALVE. 
STEAM  NOZZLE. 

ANTI-PRIMING 

PIPE. 
WATER  GAUGE. 

STEAM  GAUGE. 


MOUNTINGS  FOE  BOILEE. 

A  set  of  suitable  fire-frames  and  doors  to  be  fitted  on  the 
front  end  of  the  boiler  and  each  door  shall  be  provided 
with  a  sliding  shutter  for  the  admission  of  a  proper 
quantity  of  air  for  the  prevention  of  smoke,  also  cast-iron 
hearth  plates,  bearing  bars,  fire  bars  of  suitable  length, 
cast-iron  damper  and  frame,  and  ash-pit  frame  and 
plates. 

An  approved  fusible  plug  shall  be  placed  on  the  top  of 
each  furnace. 

One  blow-off  cock  to  be  supplied  with  solid  bottom  and 
packed  gland,  having  a  flange  at  each  end;  also  a  suit- 
able elbow  pipe  to  be  furnished  for  attaching  the  cock  to 
the  block  previously  rivetted  on  to  the  boiler. 
A  2£  inch  check  feed  valve  shall  be  provided,  the  valve  to 
be  loose  from  the  spindle  so  as  to  act  as  a  check  or  non- 
return valve  and  to  be  set  down  by  means  of  a  hand 
wheel  and  screw. 

Two  4-inch  safety  valves  of  the  most  approved  construc- 
tion. 

One  7-inch  junction  valve   fitted  up  with    gun-metal 
I  valve  and  seatings,  packed  gland,  hand  wheel,  etc. 
A  cast-iron  anti-priming  pipe  to  be  fixed  inside  the 
boiler  and  attached  to  the  lower  end  of  the  above  valve. 
One  set  of  brass  fittings  for  duplex  glass  water-gauge 
with  two  glass  tubes  for  the  same. 
One  6-inch  steam  pressure  gauge  of  best  construction. 


CHAPTER     V. 

INTERNALLY  FIRED  PORTABLE,  LOCOMOTIVE  AND  MARINE  BOILERS. 

Internally  fired  upright  tubular  boilers  are  not  often  used  for  station- 
ary work  unless  the  water  is  exceptionally  good,  on  account  of  the  difficulty 
of  cleaning  and  examination,  and  the  great  liability  to  form  scale  or  to  cor- 
rode near  the  water  line,  and  they  will  foam  when  crowded.  Many 
devices  of  submerged  smoke  chambers,  thus  reducing  the  length  of  the 
tubes  and,  of  course,  reducing  the  heating  surface,  have  been  tried,  and 
we  £nd  a  good  example  in  the  upright  tubular  boiler  recommended  by  the 
Hartford  Boiler  Insurance  Company  shown  in  the  last  chapter. 

Among  portable  boilers,  and  classing  with  them  the  boilers  for  launches 
and  fire  engines,  we  have  many  varieties.  The  tubular  upright  with  cylin- 
drical furnace,  or  the  horizontal  with  rectangular  furnace,  are  the  most 
usual.  One  of  the  simplest  boilers  ever  made  is  a  cylindrical  shell  with  a 
conical  internal  furnace,  with  the  upper  head  flanged  to  shell  and  upper 
portion  of  cone;  the  stack  is  attached  directly  to  the  top  of  the  cone,  which 
of  course,  is  truncated.  This  boiler  was  used  by  the  Lane  &  Bodley  Com- 
pany, of  Cincinnati,  Ohio. 

The  locomotive  boiler  has  a  cylindrical  shell  continued  beyond  the 
front  head,  making  a  smoke  box,  and  with  a  rectangular  furnace  of  consid- 
erable depth,  surrounded  on  all  but  the  bottom  side  by  a  second  box  with 
four  flat  sides  and  a  semi-circular  shell  top;  the  sides  are  tied  together  by 
stay  bolts,  and  the  top  held  up  by  cross  bars  .from  which  it  is  slung, 
or  by  stays  from  the  shell  above,  the  latter  practice  coming  into  favor  with 
bad  water  as  promoting  a  better  circulation  of  water  and  depositing  less 
scale. 

We  select  for  our  illustrations  the  boiler  of  a  passenger  engine  built 
by  Mr.  Jacob  Johann,  General  Master  Mechanic  of  the  Wabash,  St.  Louis  & 
Pacific  Railway,  with  its  specifications,  and  the  boiler  of  a  freight  engine 
built  for  the  Missouri  Pacific  Railway,  by  the  Baldwin  Locomotive  Works, 
for  Mr.  John  Hewitt,  Superintendent  of  Motive  Power,  with  accompanying 
description. 

The  boilers  used  on  the  steamboats  on  the  Hudson,  or  North  Eiver,  are 
of  a  peculiar  type.  With  a  locomotive  furnace  or  with  a  cast-iron  "front,"' 
with  top  flat  or  arched  with  two  or  more  water  legs  with  a  set  flues  or  large 
tubes  with  or  without  combustion  chamber,  and  with  a  considerable  length 
of  shell;  with  a  smoke  or  back  connection  with  return  tubes,  or  small  flues 
overhead  to  a  breeching  or  uptake.  The  distinguishing  feature  from  the 
English  practice,  being  the  use  of  flat  stayed  surface  in  the  furnace  and 
length  of  barrel,  while  the  English  or  regular  marine  boiler  uses  a  cylin- 


INTERNALLY  FIRED  BOILERS,  ETC. 


103 


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104  STEAM  MAKING;  OR,  BOILER  PRACTICE. 


drical  furnace  tube  of  large  diameter  and  short  length  with  back  connec- 
tion and  with  small  return  tubes  above.  According  to  the  size  of  boiler 
there  are  used  one,  two,  three,  four,  or  six  furnace  tubes.  The  single  fur- 
nace is  found  inconvenient  for  cleaning  as  taking  in  too  much  cold  air  at 
once,  loosing  steam  in  the  operation.  The  size  of  the  boiler  used  has  been 
gradually  increased  and  so  also  the  pressure  until  we  find  on  shells  16  feet 
in  diameter  pressures  as  high  as  90  pounds  per  square  inch  carried  as  the 
working  pressure. 

SPECIFICATIONS  FOB  LOCOMOTIVE  BOILER  OF  ENGINE  NO.  152. 
WABASH,  ST.  Louis  &  PACIFIC  BAIL  WAY. 

General  dimensions  of  engine.— 

Cylinder 17  X  24  inches 

Driving  wheels  diameter 5  ft.  9% 

Inletports i&  X  12^      " 

Steam  ports 1M  X  16 

Exhaust  port 3  X  16 

Width  of  bridges 1M      " 

Tank  capacity -. 3,000  gals. 

Weight  on  driving  wheels 51,000  Its. 

Weight  of  engine  with  three  gauges  of  water 80,000    " 

Boiler  and  fire-lox  of  steel.    Tubes  of  wrought-iron.    Fuel,  soft  coal— 

Diameter  inside  barrel  of  boiler 52  inches 

Length  of  fire-box 66 

Width  of  fire-box 34% 

Height  of  tire-box  at  front  end 70 

Height  of  fire- box  at  back  end 64^ 

160  tubes  2-inch  outside  diameter,  length lift.  6 


Heating  surface  in  fire-box  less  tube  area 99.5  sq  ft. 

Heating  surface  tubes  outside 963.4 

Total 1062.9 

Firegrate  area 15.6 

Fire  grate  area  air  openings 5.6 

Ratio  heating  surface  to  grate  area 68.3 

Ratio  grate  area  to  flue  area 2.47 

Water  capacity  with  two  gauges  or  5%-inch  above  crown 1,150  gals,  or  153.3  cu  ft. 

Steam  capacity  under  same  conditions 47.2 

Total..., 200.5 

SPECIFICATION  FOR  BOILER. 

Boiler. — Straight  top  made  throughout  of  best  homogeneous  steel 
plates  /B-inch  thick  (unless  otherwise  specified)  and  rivetted  with  f-inch 
rivets  spaced  not  over  1$  inch  between  centers.  All  longitudinal  seams 
double  rivetted  and  welted,  all  circular  seams  single  rivettsd  and  welted 
around  the  bottom  to  above  water  line. 

Pressure. — 150  pounds  per  square  inch. 

Waist. — Inside  diameter  at  smoke-box  end  52  inches  and  at  fire-  box 
end  53|  inches.  Side  sheet  of  fire-box  shell  f-inch  in  thickness,  and  ex- 
tending to  the  top,  forming  a  butt  joint  at  crown,  and  over  these  an  extra 
crown  sheet  f-inch  in  thickness  is  placed,  extending  down  far  enough  on 
each  side  to  receive  all  the  fire-box  crown  stays.  This  extra  crown  sheet 
is  rivetted  to  the  side  sheet  on  each  side  of  the  butt  joint  formed  by  them 


• 
INTERNALLY  FIRED  BOILERS,  ETC.  105 

at  the  crown,  and  near  the  lower  edges  of  this  extra  sheet.  Dome  28  in- 
ches in  diameter  inside  and  28  inches  high  above  boiler,  fitted  with  cast- 
iron  ring  and  cover,  so  arranged  with  slotted  flanges  that  bolts  may  be 
used  instead  of  studs.  Center  line  of  dome  situated  7  feet  7  inches  ahead 
of  the  back  face  of  back  head  of  boiler,  the  placing  of  dome  so  far  ahead 
being  necessitated  by  the  system  of  staying  employed. 

Smoke-box  is  52£  inches  diameter  inside  and  33  inches  long  from  cen- 
ter line  of  rivets,  securing  the  junction  of  smoke-box  and  waist,  and  the 
front  end.  Length  of  boiler  over  all,  20  feet  6  inches. 

Tubes. — Of  No.  11  lap-welded  charcoal  iron  with  copper  ferrules  at  both 
ends.  Tubes  160  in  number,  2  inches  outside  diameter,  11  feet  6  inches 
long,  separated  by  f-inch  bridges  in  fire-box  flue  sheet,  and  by  g-inch 
bridges  in  front  flue  sheet  to  provide  for  a  more  perfect  water  circulation. 

Fire-box.— Of.  steel  arched  and  sloping,  with  round  corners,  box  66 
inches  long,  and  35|  inches  wide,  inside.  Height  at  front  end  70  inches,  at 
back  end,  64J  inches  inside  measure,  top  sloped  1  inch  to  1  foot.  All  plates 
thoroughly  annealed  after  flanging.  The  flue  sheet  ^-inch,  crown  sheet 
f-inch,  side  and  fire-door  sheets  f§  of  an  inch  in  thickness.  Water  spaces 
3£  inches  all  round  at  the  mud  ring,  increasing  to  4  inches  near  the  crown 
sheet.  This  increase  made  by  closing  in  the  side  and  fire-door  sheets  for 
the  sides  and  back,  and  by  setting  out  the  throat  sheet  for  the  front. 
Stay  bolts  are  |  of  an  inch  in  diameter  screwed  in  and  rivetted  to  sheets 
and  not  over  4|  inches  thick  from  centre  to  centre.  Fire  door  opening 
formed  by  a  special  oval  ring  rivetted  to  outward  flanges  on  outside  and 
inside  sheets. 

Crown  Staying. — Crown  sheet  arched  transversely  with  a  radius  of  35 
inches,  with  round  corners  of  13  inches  radius  at  flue  sheet  end  and  10 
inches  radius  at  fire  door  sheet  end.  Crown  stays  of  1-inch  Sligo  iron  up- 
set at  one  end  to  admit  of  i-inch  thread  spaced  longitudinally  4g  inches, 
and  transversely  5|  inches  apart  on  the  crown  sheet.  The  stay  holes  in  the 
boiler  crown  are  so  located  that  the  stays  enter  both  the  inside  and  outside 
crowns  at  the  same  angle  longitudinally.  The  obliquity  at  which  they  en- 
ter the  outside  crown  transversely,  especially  the  lower  rows,  being  com- 
pensated for  by  the  double  sheets  forming  the  outside  crown.  Even  the 
stay  having  the  greatest  obliquity  is  by  this  means  provided  with  ample 
thread  connection  in  the  boiler  crown.  *  The  fire  box  crown  is  tapped  out 
to  1  inch  thread,  and  the  boiler  crown  to  IJ-inch  thread,  the  number  of 
threads  to  the  inch  being  the  same  in  each  case,  special  taps  and  reamers 
being  employed  for  this  purpose.  The  stays,  after  being  screwed  into 
place  are  cut  off  within  ^  of  an  inch  of  the  inside  and  outside  crowns  and 
rivetted  over  with  a  few  well  directed  blows  of  a  hammer. 

Dome.— The  dome  is  28  inches  inside  diameter  and  f  of  an  inch  thick, 
the  base  is  flanged  out  to  fit  the  shell,  and  the  shell  is  flanged  up  to  fit  in- 
side the  dome,  a  wrought-iron  welded  ring  5  inches  by  1  inch  thick  is 
placed  on  the  inside  of  the  shell  and  rivetted  to  dome  with  rivets  If  inch 
centres,  1§  inches  from  corner  of  flange;  a  second  row  of  rivets  2|  inches 


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INTERNALL  Y  FIRED  BOILERS*  ETC.  l  O7 

from  flange,  and  4-inch  centres  connects  ring  with  shell,  while  a  row,  4- 
inch  centres,  connects  flange  on  shell  to  dome. 

Boiler  Staying. — The  back  head  and  front  flue  sheet  are  well  stayed  by 
angle  gusset  braces  made  of  ^g-inch  steel  plates,  the  double  angle  iron 
connections  for  these  braces  also  being  made  of  the  same  material  as  they 
answer  the  purpose  much  better  than  if  made  of  merchant  angle  iron. 

Cleaning  Arrangements. — Cylinder  part  of  boiler  is  fitted  with  a  boiler 
washer  immediately  back  of  front  flue  sheet  with  a  man-hole  just  back  of 
washer  for  convenience  in  examining  boiler,  cleaning  plugs  in  corners  of 
fire  box,  hand-hole  plates  in  front  leg;  and  blow-off  cock  in  back  end.  The 
boiler  washer  consists  of  two  horns  curved  to  fit  shell  connected  with  noz- 
zle provided  with  check  valve  passing  through  bottom  of  shell  flange  and 
washer  secured  to  same.  A  set  of  nozzles  point  upward,  and  another  set 
backwards.  The  boiler  is  always  washed  out  under  pressure  and  then 
when  empty. 

Throttle.— Balanced  poppet  throttle  valve  of  cast-iron.  Throttle  pipe 
of  cast-iron  with  flange  or  water  shed  on  outside  of  it.  Dry  pipe  of 
wrought  iron  6  inches  inside  diameter. 

Grates.— Of  cast-iron  rocking  finger  bar  pattern,  arranged  to  work 
from  cab,  fingers  9£  inches  long  from  centre  of  bar  to  end  of  fingers.  Ash 
pan  fitted  with  double  dampers.  All  steam  used  except  for  running  the 
engine  is  taken  from  a  brass  stand  with  one  opening  from  boiler  provided 
with  check  valve  opened  by  an  eccentric,  and  which  closes  by  the  pressure 
inside  unless  held  open  which  would  happen  if  by  accident  the  stand  was 
knocked  off. 

Feed  Water. — Supplied  by  two  No.  16  Hue  injectors  in  the  cab,  one  on 
each  side  of  boiler,  water  enters  on  shell  22  inches  from  front  head 
through  check  valves. 

DESCRIPTION  OF  BOILER  FOR  "CONSOLIDATION  LOCOMOTIVE"  FOR  THE 
MISSOURI  PACIFIC  RAILROAD. 

Shell,  diameter  outside  smallest  sheet  56;  shell,  length,  12  ft.  M-in.,  thickness  7/16-in. ; 
material,  steel;  shell  of  smoke  box  %-in.  thick;  wrought  iron. 

Thickness,  tube  sheets %  inch. 

fire-box,  side  sheets 7/16    " 

fire-box,  crown  sheets 7/16    " 

fire-box,  back  sheets  7/16    " 

Material Homogeneous  steel. 

Number  of  tubes 198 

Diameter  outside  of  tubes , 2  inches. 

Thickness No.  11,  B.  W.  G. 

Fire-box  stay  bolts,  (outside) %  inch. 

Head  stay  bolts,  (outside) 1    " 

Crown  bar 6X^    " 

Crown  stays %    " 

The  older  marine  boilers  were  generally  rectangular  in  form  with  stayed 
furnaces,  and  present  type  has  developed  from  them.  The  only  division  of 
these  boilers  which  we  can  make  is  based  on  the  number  of  furnaces,  and 
whether  they  are  fired  from  one  or  both. 


108 


STEAM  MAKING;  OR,  BOILER  PRACTICE. 


;UNI 

INTERNALLY  FIRED  BOILERS,  ETC. 


Marine  boilers  with  a  single  furnace  are  now  confined  to  very  small 
boilers  for  steam  launches  as  it  has  been  found  by  experience  that  it  is 
difficult  to  maintain  steam  while  the  fires  are  being  cleaned  as  the  air  in- 
troduced while  cleaning  lowers  the  steam  on  the  entire  heating  surface. 
This  type  of  boiler  was  largely  used  in  the  United  States  Navy,  but  is  be- 
ing replaced  by  those  with  two  and  three  furnaces  as  fast  as  practicable. 

The  double  furnace  marine  boiler  which  we  illustrate  is  one  of  ten 
placed  in  Her  Britannic  Majesty's  corvette  "Kover. "  Each  boiler  is  11  feet  10 
inches  in  diameter  and  9  feet  6  inches  long  with  228  brass  tubes  3  inches 
in  diameter.  The  total  heating  surface  in  the  ten  boilers  is  12,700  square 
feet  and  the  total  grate  surface  is  510  square  feet.  The  shells  are  double 
ri vetted  throughout,  the  longitudinal  seams  having  butt  joints  with  butt 
straps  inside  and  out.  The  pressure  carried  on  trial  trip  was  70  pounds 
per  square  inch.  The  thickness  of  plates  is  not  stated  and  the  material, 
probably  iron  |  of  an  inch  thick,  with  furnace  and  connections  ^-  of  an 
inch,  with  tube  plates  f  of  an  inch;  end  plates  f  of  an  inch. 

The  double  furnace  type  is  usually  preferred  for  shells  8  to  10  feet  in 
diameter;  while  for  larger  diameters  three  furnaces  are  usually  preferred. 

The  three  furnace  boiler  selected  as  our  illustration  is  one  of  the  first 
steel  marine  boilers  built  and  was  selected  as  an  exceedingly  good  exam- 
ple in  every  way  of  a  very  judicious  design. 

The  diameter  of  shell  is  13  feet  3  inches,  the  length  10  feet  8  inches: 
the  shell  plates  are  ^  of  an  inch,  the  end  plates  &  of  an  inch.  The  fur- 
nace and  combustion  chamber  plates  are  5^  of  an  inch,  and  the  front  and 
back  tube  sheets  ^  of  an  inch  in  thickness.  The  screw  stay  bolts  are  1§  inch 
in  diameter,  and  the  tie-rods  in  the  steam  space  are  If  inches  in  diameter 
with  external  and  internal  nuts  and  with  an  external  washer  plate  rivetted 
to  the  end  plate.  The  shell  joints  are  all  double  rivetted,  the  longitudinal 
seams  with  double  butt  straps,  Ij^-inch  steel  rivets,  4  inch  centres.  The 
lap  joints  are  3^  centres.  The  back  end  plates  are  lapped  and  bent.  The 
lap  for  double-rivetted  seam  is  5  inches.  The  furnace  tubes  are  3  feet  3 
inches  in  external  diameter  and  joined  with  double  butt  staps.  The  com- 
bustion chamber  stays  are  9  inch  centres.  The  dome  stands  6  ft.  10|  in. 
from  the  shell  of  the  boiler  and  is  3  ft.  8  in.  inside  diameter  united  to  the 
shell  by  a  short  neck.  The  steam  is  taken  from  the  dome  by  steam  pipe, 
not  shown  in  drawing.  There  are  244  solid  drawn  tubes  of  the  same  ma- 
terial as  the  shell  and  rivets,— that  is  of  Landore- Siemens  steel.  The  total 
heating  surface  is  1880  square  feet  and  the  pressure  for  which  the  boiler 
was  designed  is  65  pounds  to  the  square  inch. 

The  boiler  was  built  after  a  long  and  careful  series  of  experiments, 
of  which  we  give  in  another  place  the  conclusions. 

Four  furnace  single  end  boilers  have,  we  believe,  been  used  to  some 
extent  but  we  have  no  knowledge  of  them.  The  great  diameter  of  shell  or 
small  diameter  of  furnace  tubes  requires  the  use  of  either  low  pressure 
steam  or  fires  of  moderate  thickness  for  which  we  should  suggest  the  use 
of  anthracite  instead  of  soft  coal. 

The  four  furnace  double-ended  boiler  selected  for  illustration,  is  one 


110 


STEAM  MAKING;    OR,  BOILER  PRACTICE. 


STEEL    BOILER, 


Built  by  the  Wallsend  Slipway  Company,  Newcastle-upon-Tyne. 


INTERNALLY  FIRED  BOILERS,  ETC. 


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TRANSVERSE  SECTION  THROUGH  FURNACES  AND  TUBES. 


1 2      MetriiS 


NOTE.— This  scale  also  applies  to  cuts  on  opposite  page. 


1 1 2  STEAM  MA  KING;  OR,  BOILER  PR  A  CTICE. 

of  three  placed  in  the  steamship  "Assyrian  Monarch.'  The  boiler  is  12  ft. 
3  in.  in  diameter,  and  18  ft.  6  in.  long,  with  corrugated  furnace  tubes,  3  ft. 
9  in.  diameter,  the  latter  of  Don  iron,  the  remainder  is  of  steel,  by  Messrs. 
John  Brown  &  Company,  Sheffield.  The  shell  plates  are  £J  of  an  inch,  the 
end  plates  §£  of  an  inch  above,  and  f  of  an  inch  below,  and  the  tube  plates 
are  f  of  an  inch,  and  the  corrugated  tubes  and  combustion  chambers  are  \- 
inch  in  thickness.  The  double -ri vetted  longitudinal  seams  have  1-inch 
holes  and  J|-inch  rivets,  3J|  inches  centres.  The  butt  straps  are  9  inches 
while  the  thickness  is,  for  those  of  the  central  ring  ^  of  an  inch  inside, 
and  ^  of  an  inch  outside,  and  for  the  two  end  rings  ||  of  an  inch  inside, 
and  j9g  of  an  inch  outside.  The  other  two  rings  have  ^  of  an  inch  inside, 
and  |^  of  an  inch  outside.  The  ring  seams  have  4J£  inches  thick.  The 
rivets  1  inch  in  l^  inch  holes  and  3g  inch  centres  double-rivetted.  None 
of  the  holes  are  punched,  but  when  possible,  drilled  in  place  after  the 
sheets  are  bent  and  put  together.  Each  ring  of  the  shell  is  made  of  three 
plates.  The  flange  plates  are  all  annealed  after  flanging.  The  long  stay 
rods  of  wrought  iron,  the  upper  row  2|  inches  and  the  lower  row  2|  inches 
in  diameter.  The  washer  plates  are  9  inches  in  diameter  and  |£  of  an  inch 
thick,  ri  vetted  to  the  end  plates.  The  screw  bolt  stays  are  1£  inch  exter- 
nal, l^g  inch  effective  diameter  of  steel  screwed  into  the  plates  and  with 
nuts  also  at  each  end.  There  are  388  wrought  iron  tubes  3|  inches  exter- 
nal diameter,  6  ft.  7  in.  long,  44  are  stay  tubes  2|  inches  inside  diameter, 
being  ^  of  an  inch  thick  under  the  threads.  These  are  screwed  and 
headed  over  in  the  back  tube  plates  while  they  have  nuts  inside  and  out  at 
the  other  end. 

The  grates  are  5  ft.  6  in.  long,  and  have  an  area  each  20.6  sq.  ft.  in  each 
furnace  or  82.5  sq.  ft.  for  one  boiler,  and  247.5  sq.  ft.  in  all.  The  tube  sur- 
face in  each  boiler  is  2140  sq.  ft.,  and  the  total  heating  surface  is  2601  sq. 
ft.  or  7803  sq.  ft.  for  the  three  boilers.  The  pressure  allowed  by  the  Board 
of  Trade  and  Lloyd's  is  80  pounds  per  square  inch. 

The  machinery  and  vessel  were  built  by  Earle's  Shipbuilding  and  En- 
gineering Company,  of  Hull,  for  the  Koyal  Exchange  Shipping  Company, 
of  London,  for  the  New  York  and  London  trade  in  1881. 

The  last  example  of  marine  boilers,  which  we  give,  is  one  of  three 
oval  ones  for  the  steamship  "Mexican. "  The  three  are  set  athwart -ships  with 
their  center  lines  fore  and  aft.  The  boilers  are  each  12  feet  10  inches  wide, 
16  feet  6  inches  high,  and  17  feet  6  inches  long,  and  work  at  90  pounds 
pressure.  There  is  one  stack,  and  each  boiler  has  three  furnaces  at  each 
end  3  feet  4  inches  diameter.  The  furnace  tubes  are  of  steel  ^g-inch  thick, 
and  corrugated  on  Fox's  patent.  There  is  placed  over  the  center  boiler  a 
steam  drum  21  feet  long  and  5  feet  diameter.  There  are  in  each  boiler  440 
tubes,  6  feet  9  inches  between  tube  sheets,  3£  inches  outside  diameter, 
No.  8  wire  gauge.  The  stay  tubes  are  3|  inches,  with  ends  swelled  to  3£ 
inches.  The  ring  sheets  are  g-inch  steel,  and  are  in  length  in  order, 
3  feet  2|  inches,  3  feet  lOf  inches,  4  feet  7£  inches,  3  feet  10|  inches,  and  3 
feet  2|  inches.  The  top  end  plates  are  |£-inch,  with  a  re-enforce  of 
£-inch,  shown  by  dotted  lines.  The  end  tube  plates  are  f-inch  thick, 


INTERNALLY  FIRED  BOILERS,  ETC.  • 


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INTERNALLY  FIRED  BOILERS,  ETC.  117 

and  the  bottom  end  plates  are  f-inch.  The  tube  plates  in  the  com- 
bustion chamber  are  f-inch  thick.  There  are  thirty  stay-bolts  passing 
from  head  to  head  of  boiler,  with  27e-inch  body,  and  2|-inch  screwed  ends, 
with  nuts  and  washers  inside  and  out.  There  are  forty  transverse  stays 
holding  the  flat  sides,  2|  inches  in  body  and  2^-inch  screwed  ends,  with  nuts 
and  washers  inside  and  out.  The  tubes  are  spaced  so  as  to  make  room  for 
these  last  bolts.  The  stay  tubes  are  screwed  in  the  tube  plates,  but  do  not 
have  nuts  on  them.  The  combustion  chambers  are  stayed  by  bolts  If -inch 
at  bottom  of  threads  for  the  center  row,  and  1^-inch  for  the  other  four 
rows.  The  side  sheets  of  combustion  chambers  are  £-inch  thick.  The  top 
sheets  are  held  by  bolts  from  crown  bars  10  inches  by  |-  inch  double,  of  which 
five  sets  are  slung  by  two  IJ-inch  eye-bars  with  fork-eyes  from  the  sheet. 
The  center  of  the  drum  is  6  feet  3  inches,  and  is  of  ^-inch  metal. 

In  the  three  boilers  there  are  10,000  square  feet  of  heating  surface  and 
3,100  cubic  feet  of  steam  room,  including  the  drum,  and  404.5  square  feet 
of  grate. 

A  man -head  at  each  end  gives  admission  under  the  furnaces,  and  it  is 
to  be  supposed  there  is  to  be  admission  above  them.  The  water  spaces 
between  the  tubes  are  12  inches  in  the  clear,  which  admits  of  a  man  pass- 
ing from  the  top  of  the  furnace  up  to  the  upper  portion  of  the  shell.  The 
boilers  are  the  best  examples  of  accessibility  that  we  have  seen.  They 
were  built  by  the  Southwick  Engine  Works,  Sunderland,  in  1882. 

For  large  boilers  we  find  this  type  quite  a  favorite  one,  and  we 
mention  the  Cunard  steamship  "Servia,"  which  carries  six  double  ended 
boilers,  and  one  single  ended,  with  three  furnaces,— thirty-nine  in  all.  The 
furnace  tubes  are  4  feet  2  inches  by  6  feet  9  inches  long,  with  a  grate  surface 
of  1,050  square  feet,  and  a  total  heating  surface  of  27,000  square  feet.  The 
boilers  are  14  feet  10  inches  wide,  18  feet  high,  and  18  feet  3  inches  long, 
of  Siemens  steel.  The  furnace  tubes  are  corrugated  and  are  also  of  steel. 
The  working  pressure  is  90  pounds. 

Most  steam  fire  engine  boilers  are  of  the  upright  tubular  class. 
The  London  builders,  Messrs.  Shand  &  Mason,  use  a  rectangular  chamber 
traversed  by  nearly  horizontal  tubes  above  a  circular  fire-box  and  of  course 
a  circular  shell.  The  Silsby  Company,  of  New  York,  use  a  vertical  tubular 
with  hanging  tubes  in  the  fire-box,  with  internal  circulating  tubes  there- 
in; but  the  most  successful  in  practice  has  been  the  "Latta,"  built  by  the 
Ahrens  Manufacturing  Company,  of  Cincinnati:  this  boiler  has  been  used 
for  over  twenty-eight  years,  and  although  the  use  of  a  fire  engine  is  not 
continuous,  yet  eighteen  of  these  boilers  were  in  continuous  service  for 
forty-nine  hours  at  a  fire  in  Cincinnati,  on  July  7  and  8,  1882,  without  any 
trouble.  Their  service  in  St.  Louis,  where  the  water  is  very  muddy,  has 
been  very  successful,  and  in  1881,  there  were  twenty-one  of  them  in  use. 

The  peculiar  features  of  this  boiler  are  clearly  shown  in  the  accom- 
panying illustrations.  The  boiler  consists  of  a  double  shell  within  which 
is  the  furnace,  and  between  which  is  the  steam  and  water  space.  A  nest 
of  wrought  iron  pipes  is  placed  in  the  upper  part  of  the  furnace,  forming 
four  coils  starting  from  a  single  pipe  and  fed  from  the  water  space  by  a 


118 


STEAM.  MAKING;    OR,  BOILER  PRACTICE. 


TOP  VIEW. 


BOTTOM  VIEW 


THE    "LATTA"    BOILER. 


THE  DESIGN,  CONSTRUCTION,  ETC.  *  119 

separate  circulating  pump,  discharging  a  mixture  of  steam  and  water  into 
the  upper  part  of  the  shell,  which  thus  acts  as  a  separator,  the  water  fall- 
ing through  the  steam  to  the  lower  part  of  the  shell.  The  pipes  are  kept 
clean  by  the  active  current  induced  by  the  pump.  From  thirty  to  forty 
gallons  of  water  are  used  at  a  time.  A  variable  exhaust  from  the  engine 
controls  the  draft,  and  the  extent  of  pipe  surface  gives  a  very  rapid  for- 
mation of  steam.  The  engines  are  guaranteed  to  throw  water  in  four 
minutes  from  the  lighting  of  the  fires,  with  cold  water. 

The  Herreshoff  Manufacturing  Company,  of  Bristol,  B.  I.,  have  used  a 
form  of  boiler  for  small  steamboats,  which  differs  from  the  "Latta"  in 
using  a  spiral  coil  of  welded  pipe,  a  very  great  improvement  over  the 
jointed  form  shown  in  the  "Latta,"  and  the  use  of  a  small  separator,  in- 
stead of  the  shell,  which  can  hardly  be  called  an  improvement  for  small 
shells.  These  boilers  have  been  measurably  successful  with  good  water  at 
sea,  but  we  know  of  only  three  tried  in  Western  waters.  A  small  one  on 
the  Upper  Missouri  was  successfully  used  by  the  United  States  Engineer  De- 
partment for  a  small  boat,  while  the  other  two,  one  at  the  Sabula  Draw 
Bridge,  arid  one  in  St.  Louis,  did  not  give  satisfaction,  soon  burning  out. 
The  small  boilers,  the  "Latta"  shell  and  the  Herreshoff  coil,  would  prob- 
ably work  well  for  continuous  service  with  good  water,  but  for  bad  water 
their  use  will  be  restricted  to  "emergency  duty." 


CHAPTER     VI. 

THE  DESIGN,  CONSTRUCTION  AND  STRENGTH  OF  BOILERS. 

The  features  which  are  most  important  appear  to  be  to  provide: 

1.  Safety;  or  strength. 

2.  Durability;  or  strength  in  the  future. 

3.  Convenience  in  cleaning  and  inspection. 

4.  Capacity  to  do  the  required  work.    We  place  this  last  as  requiring 
less  attention  than  the  others. 

The  strength  of  cylindrical  shells  is  a  very  simple  matter  from  the 
proportion.  The  thickness  of  the  shell  is  to  radius  of  the  shell  as  the 
pressure  inside  the  shell  is  to  the  tension  around  the  shell.  The  thick- 
ness and  radius  being  in  inches,  the  pressure  in  pounds  per  square  inch, 
the  tension  will  be  in  pounds  upon  a  square  inch  of  section.  The  tension 
along  the  shell  is  one-half  that  around  the  shell. 

The  thickness,  diameter  and  pressure  allowed  by  law  on  steamboats  in 
the  United  States  is  given  in  the  accompanying  extracts  from  the  laws  of 
the  United  States  relative  to  the  inspection  of  steamboats,  taken  from 
pamphlet  form  2,100,  laws  governing  the  steamboat  inspection  service.  Ke- 
vised  statutes  of  the  United  States,  dated,  1882,  and  from  the  "General  rules 
and  Regulations  of  the  Board  of  Supervising  Inspectors  of  Steam  Vessels, " 
revised  to  1880. 

TITLE  LII.    REGULATION  OF  STEAM  VESSELS.     CHAPTER  I.,  INSPECTION. 

SECTION  4399.  Every  vessel  propelled  in  whole  or  in  part  by  steam 
shall  be  deemed  a  steam  vessel  within  the  meaning  of  this  title. 

SEC.  4400.  All  steam  vessels  navigating  any  waters  of  the  United 
States  which  are  common  highways  of  commerce  or  open  to  general  or 
competitive  navigation  excepting  public  vessels  of  the  United  States,  ves- 
sels of  other  countries  and  boats  propelled  in  whole  or  in  part  by  steam  for 
navigating  canals  shall  be  subject  to  the  provisions  of  this  title. 

SEC.  4418.  The  local  inspectors  shall  also  inspect  the  boilers  of  all 
steam  vessels  before  the  same  shall  be  used,  and  once  at  least  in  every  year 
thereafter.  They  shall  subject  all  boilers  to  the  hydrostatic  pressure,  and 
shall  satisfy  themselves  by  thorough  examination  that  the  boilers  are  well 
made,  of  good  and  suitable  material;  that  the  openings  for  the  passage  of 
steam  and  water,  respectively,  and  all  pipes  and  tubes  exposed  to  heat  are 
of  proper  dimensions  and  free  from  obstructions;  that  the  spaces  between 
and  around  the  flues  are  sufficient;  that  the  flues  are  circular  in  form;  that 


THE  DESIGN,  CONSTRUCTION,  ETC.  121 

the  fire  line  of  the  furnace  is  at  least  2  inches  below  the  prescribed  mini- 
mum low  water  line  of  the  boilers;  that  the  arrangement  for  delivering 
the  feed  water  is  such  that  the  boilers  cannot  be  injured  thereby,  and  that 
such  boilers  and  machinery  and  the  appurtenances  may  be  safely  em- 
ployed in  the  service  proposed  in  the  written  application  without  peril  to 
life.  They  shall  also  satisfy  themselves  that  the  safety  valves  are  of  suit- 
able dimensions,  sufficient  in  number  and  well  arranged,  and  that  the 
weights  of  the  safety  valves  are  properly  adjusted  so  as  to  allow  no  greater 
pressure  in  the  boilers  than  the  amount  prescribed  in  the  inspection  cer- 
tificate; that  thore  is  a  sufficient  number  of  gauge  cocks  properly  inserted, 
and  to  indicate  the  pressure  of  steam,  suitable  steam  registers  that  will 
correctly  record  each  excess  of  steam  carried  above  the  prescribed  limit, 
and  the  highest  point  attained;  and  that  there  are  reliable  low  water 
gauges,  and  that  the  fusible  metals  are  properly  inserted  so  as  to  fuse  by 
the  heat  of  the  furnace  whenever  the  water  in  the  boilers  falls  below  its 
prescribed  limits:  arid  that  adequate  and  certain  provision  is  made  for  an 
ample  supply  of  water  to  feed  the  boilers  at  all  times,  whether  such  vessel 
is  in  motion  or  not,  so  that  in  high  pressure  boilers  the  water  shall  not  be 
less  than  4  inches  above  the  top  of  the  flues,  and  that  means  for  blowing 
out  are  provided,  so  as  to  thoroughly  remove  the  mud  and  sediment  from 
all  parts  of  the  boilers  when  they  are  under  pressure  of  steam,  In  sub- 
jecting to  the  hydrostatic  tests  boilers  usually  designated  as  high  pressure 
boilers  the  inspectors  shall  assume  110  pounds  to  the  square  inch  as  the 
maximum  pressure  allowable  as  a  working  power  for  a  new  boiler  of  42 
inches  in  diameter,  made  in  the  best  manner  of  inspected  iron  plates  one- 
fourth  of  an  inch  thick,  and  of  a  quality  required  by  law  and  shall  rate  the 
working  power  of  all  high  pressure  boilers  whether  old  or  new  according 
to  their  strength  compared  with  this  standard,  and  in  all  cases  the  test 
applied  shall  exceed  the  working  power  allowed  in  the  ratio  of  165  to  110. 
In  subjecting  to  the  hydrostatic  tests  boilers  usually  designated  and 
known  as  low  pressure  boilers,  the  inspectors  shall  allow  as  a  working 
power  for  each  new  boiler  a  pressure  of  only  three -fourths  the  num- 
ber of  pounds  to  the  square  inch  to  which  it  has  been  subjected  by 
the  hydrostatic  tests,  and  for  which  it  has  been  found  to  be  sufficient. 
Should  the  inspectors  be  of  the  opinion  that  any  boiler  by  reason  of  its 
construction  or  material  will  not  safely  allow  so  high  a  working  pressure 
as  is  above  described,  they  may,  for  reasons  to  be  stated  specially  in  their 
certificate,  fix  the  working  pressure  of  such  boiler  at  less  than  three- 
fourths  of  the  test  pressure.  All  boilers  used  on  steam  vessels  and  con- 
structed of  iron  or  steel  plates,  inspected  under  the  provisions  of  section 
4430  shall  be  subjected  to  a  hydrostatic  test  in  the  ratio  of  150  to  the  square 
inch  to  100  pounds  to  the  square  inch  of  the  working  steam  pressure  allowed. 
No  boiler  or  pipe  nor  any  of  the  connections  therewith  shall  be  approved 
which  is  made  in  whole  or  in  part  of  bad  material,  or  is  unsafe  in  its  form 
or  dangerous  from  defective  workmanship,  age,  use  or  other  cause. 

By  an  Act  of  Jan.  6, 1874,  the  pressure  allowed  boats  on  the  Mississippi 
River  was  modified  as  follows: 


122  STEAM  MAKING;  OR,  BOILER  PRACTICE. 

AN  ACT,  Relating  to  the  Limitation  of  Steam  Pressure  of  Vessels  Used 
Exclusively  for  Towing  and  Carrying  Freight  on  the  Mississippi  River 
and  its  Tributaries. 

Be  it  enacted  by  the  Senate  and  House  of  Representatives  of  the  United 
States  in  Congress  asssembled: 

That  the  provisions  of  an  act  entitled  "An  Act  to  Provide  for  the  Bet- 
ter Security  of  Life  on  Vessels  Propelled  in  Whole  or  in  Part  by  Steam," 
etc.,  approved  Feb.  28,  1871,  so  far  as  they  relate  to  the  limitation  of  steam 
pressure  of  steamboats  used  exclusively  for  towing  and  carrying  freight 
on  the  Mississippi  river  and  its  tributaries,  are  hereby  so  far  modified  as 
to  substitute  for  such  boats  150  pounds  of  steam  pressure  in  place  of  110 
pounds,  as  provided  in  said  act  for  the  standard  pressure  upon  standard 
boilers  of  42  inches  diameter  and  of  plates  one-quarter  of  an  inch  in 
thickness;  and  such  boats  may,  on  the  written  permit  of  the  supervising 
inspector  of  the  district  in  which  such  boats  shall  carry  on  their  business, 
be  permitted  to  carry  steam  above  the  standard  pressure  of  110  pounds, 
but  not  exceeding  the  standard  pressure  of  150  pounds  to  the  square  inch. 
Approved  Jan.  6th,  1874. 

SEC.  4419.  One  of  the  safety  valves  may,  if  in  the  opinion  of  the 
local  inspectors  it  is  necessary  to  do  so,  and  the  steam  registers  shall  be 
taken  wholly  from  the  control  of  all  persons  engaged  in  navigating  such 
vessel,  and  secured  by  the  inspectors. 

SEC.  4426.  The  hull  and  boilers  of  every  ferry  boat,  canal  boat,  yacht 
or  other  small  craft  of  like  character  propelled  by  steam  shall  be  inspected 
under  the  provisions  of  this  title.  Such  other  provisions  of  law  for  the 
better  security  of  life  as  may  be  applicable  to  such  vessels  shall  by  the 
regulations  of  the  board  of  supervising  inspectors,  also  be  required  to  be 
complied  with  before  a  certificate  of  inspection  shall  be  granted  and  no 
such  vessel  shall  be  navigated  without  a  licensed  engineer,  and  a  licensed 
pilot. 

SEC.  4427.  The  hull  and  boiler  of  every  tug  boat,  towing  boat  and 
freight  boat  shall  be  inspected  under  the  provisions  of  this  title,  and  the 
inspector  shall  see  that  the  boilers,  machinery  and  appurtenances  of  such 
vessel  are  not  dangerous  in  form  or  workmanship,  and  that  the  safety 
valves,  gauge  cocks,  low  water  alarm  indicators,  steam  gauges  and  fusible 
plugs  are  all  attached  in  conformity  to  law;  and  the  officers  navigating 
such  vessels  shall  be  licensed  in  conformity  with  the  provisions  of  this 
title  and  shall  be  subject  to  the  same  provisions  of  law  as  officers  navi- 
gating passenger  steamers. 

SEC.  4428.  Every  boiler  manufactured  to  be  used  on  steam  vessels  and 
made  of  iron  or  steel  plates  shall  be  constructed  of  plates  that  have  been 
stamped  in  accordance  with  the  provisions  of  the  title. 

SEC.  4429.  Every  person  who  constructs  a  boiler  or  steam  pipe  con- 
necting the  boilers,  to  be  used  on  steam  vessels,  of  iron  or  steel  plates 
which  have  not  been  duly  stamped  and  inspected  according  to  the  provi- 


THE  DESIGN,  CONSTRUCTION,  ETC.  123 

sions  of  this  title,  or  who  knowing  uses  any  defective,  bad,  or  faulty  iron 
or  steel  in  the  construction  of  such  boilers,  or  who  drifts  any  rivet  hole  to 
make  it  come  fair;  or  who  delivers  any  such  boiler  for  use  knowing  it  to 
be  imperfect,  in  its  flues,  flanging,  riveting,  bracing,  or  in  any  other  of  its 
parts,  shall  be  fined  $1,000,  one-half  for  the  use  of  the  informer. 

Nothing  in  this  title  shall  be  so  construed  as  to  prevent  from  being 
used,  on  any  steamer,  any  boiler  or  steam  generator  which  may  not  be 
constructed  of  ri vetted  iron  or  steel  plates,  when  the  board  of  supervising 
inspectors  have  satisfactory  evidence  that  such  boiler  or  steam  generator 
is  equal  in  strength  and  as  safe  from  explosion  as  a  boiler  of  the  best  qual- 
ity constructed  of  rivetted  iron  or  steel  plates.  ["Provided,  however,  that 
the  Secretary  of  the  Treasury  may  grant  permission  to  use  any  boiler  or 
steam  generator  not  constructed  of  rivetted  iron  or  steel  plates  upon  the 
certificate  of  the  supervising  inspector  of  the  district  wherein  such  boiler 
or  generator  is  to  be  used,  and  other  satisfactory  proof  that  the  use  of 
the  same  is  safe  and  efficient,  said  permit  to  be  valid  until  the  next  regu- 
lar meeting  of  the  supervising  inspectors  who  shall  act  thereon. "]  Amend- 
ment passed  Aug.  7th,  1882. 

SEC.  4430.  Every  iron  or  steel  plate  used  in  the  construction  of  steam- 
boat boilers,  and  which  shall  be  subject  to  a  tensile  strain,  shall  be  in- 
spected in  such  manner  as  shall  be  prescribed  by  the  Board  of  Supervis- 
ing Inspectors  and  approved  by  the  Secretary  of  the  Treasury,  EO  as  to 
enable  the  inspectors  to  ascertain  its  tensile  strength,  homogeneousness, 
toughness  and  ability  to  withstand  the  effect  of  repeated  heating  and  cool- 
ing; and  no  iron  or  steel  plate  shall  be  used  in  the  construction  of  such 
boilers  which  has  not  been  inspected  and  approved  under  the  rules. 

SEC.  4431.  Every  plate  of  boiler  iron  or  steel  made  for  use  in  the  con- 
struction of  steamboat  boilers  shall  be  left  visible  when  such  plates  are 
worked  into  boilers,  with  the  name  of  the  manufacturer,  the  place  where 
manufactured,  and  the  number  of  pounds  tensile  strain  it  will  bear  to  the 
sectional  square  inch;  and  inspectors  shall  keep  a  record  in  their  office  of 
the  stamps  upon  all  boiler  plates  and  boilers  which  they  inspect. 

SEC.  4432.  Every  person  who  counterfeits  or  causes  to  be  counter- 
feited any  of  the  marks  or  stamps  prescribed  for  boiler  iron  or  steel  plates, 
or  who  designedly  stamps  or  causes  to  be  stamped  falsely  any  such  plates, 
and  every  person  who  stamps  or  marks,  or  causes  to  be  stamped  or 
marked  any  such  iron  or  steel  plates  with  the  name  or  trade  mark  of 
another  with  the  intent  to  mislead  or  deceive  shall  be  fined  $2,000,  one- 
half  to  the  use  of  the  informer,  and  may  in  addition  thereto  at  the  dis- 
cretion of  the  court,  be  imprisoned  not  exceeding  two  years. 

SEC.  4433.  The  working  steam  pressure  allowable  on  boilers  con- 
structed of  plates  inspected  as  required  by  this  title,  when  single-rivetted 
shall  not  produce  a  strain  to  exceed  one- sixth  of  the  tensile  strength  of 
the  iron  or  steel  plates  of  which  such  boilers  are  constructed;  but  where 
the  longitudinal  laps  of  the  cylindrical  parts  of  such  boilers  are  double- 
ri vetted,  and  the  rivet  holes  have  been  fairly  drilled  instead  of  punched, 
an  addition  of  20  per  centum  to  the  working  pressure  provided  for  single- 


424  STEAM  MAKING;  OR,  BOILER  PRACTICE. 


rivetting  may  be  allowed.  Provided,  That  all  other  parts  of  such  boiler* 
shall  correspond  in  strength  to  the  additional  allowances  so  made,  and  no 
split  caulking  shall  in  any  case  be  permitted. 

SEC.  4434.  No  boiler  to  which  the  heat  is  applied  to  the  outside  of  the 
shell  thereof,  shall  be  constructed  of  iron  or  steel  plates  of  more  than  ^ 
of  an  inch  in  thickness,  the  ends  or  heads  of  the  boilers  only  excepted; 
and  every  such  boiler  employed  on  steam  vessels  navigating  rivers  flow- 
ing into  the  Gulf  of  Mexico,  or  their  tributaries  shall  have  not  less  than 
3  inches  space  between  and  around  its  internal  flues. 

SEC.  4435.  The  feed  water  shall  be  delivered  into  the  boilers  in  such 
manner  as  to  prevent  it  from  contracting  the  metal  or  otherwise  in- 
juring the  boilers.  And  when  boilers  are  so  arranged  on  a  vessel  that 
there  is  employed  a  water  connecting  pipe  through  which  the  water  may 
pass  from  one  boiler  to  another,  there  shall  also  be  provided  a  similar 
steam  connection  having  an  area  of  opening  into  each  boiler  of  at  least  a 
square  inch  for  every  2  square  feet  of  effective  heating  surface  contained 
in  any  one  of  the  boilers  so  connected,  half  the  flue  and  all  other  fire  sur- 
faces being  computed  as  effective.  Adequate  provisions  shall  be  made  on 
all  steam  vessels  to  prevent  sparks  of  flames  from  being  driven  back  from 
the  fire  doors  into  the  vessel. 

SEC.  4436.  Every  boiler  shall  be  provided  with  a  good,  well  con- 
structed safety  valve  or  valves  of  such  number,  dimensions  and  arrange- 
ments as  shall  be  prescribed  by  the  Board  of  Supervising  Inspectors  and 
shall  be  also  provided  with  a  sufficient  number  of  gauge  cocks  and  a  relia- 
ble low  water  indicator  that  will  give  alarm  when  the  water  falls  below  its 
prescribed  limits;  and  in  addition  thereto,  there  shall  be  inserted  in  a 
suitable  manner  in  the  flues,  crown  sheets  or  other  parts  of  the  boiler 
most  exposed  to  the  heat  of  the  furnace  when  the  water  falls  below  its 
prescribed  limits  a  plug  of  good  Banca  tin. 

SEC.  4437.  Every  person  who  intentionally  loads  or  obstructs  or 
causes  to  be  loaded  or  obstructed  in  any  way  or  manner,  the  safety  valve 
of  a  boiler  or  who  employs  any  other  means  or  device  whereby  the  boiler 
may  be  subjected  to  a  greater  pressure  than  the  amount  allowed  by  the 
certificate  of  the  inspectors  or  who  intentionally  deranges  or  hinders  the 
operation  of  any  machinery  or  device  employed  to  denote  the  state  of  the 
water  or  steam  in  any  boiler,  or  to  give  warning  of  approaching  danger, 
or  who  intentionally  permits  the  water  to  fall  below  the  prescribed  low 
water  line  of  the  boiler,  and  every  person  concerned  therein  directly  or 
indirectly,  shall  be  guilty  of  a  misdemeanor  and  shall  be  fined  $200  and 
may  also  be  imprisoned  not  exceeding  five  years. 


THE  DESIGN,  CONSTRUCTION,  ETC.    ' 


125 


EXTRACTS  FROM  THE  RULES  AND  REGULATIONS  OF  THE  BOARD  OF  SUPER- 
VISING  INSPECTORS  OF  STEAM  VESSELS. 

TABLE  OF  PKESSUBES  ALLOWABLE  ON  BOILERS  MADE  SINCE  FEBRUARY  28,  1872. 


Diameter  of  Boiler. 

Thickness  of  Plates. 

45,000    TEN- 
SILE 
STRENGTH. 

1-6,  7,500. 

50,000    TEN- 
SILE 
STRENGTH. 

1-6,  8,333.3. 

55,000     TEN- 
SILE 
STRENGTH. 

1-6,  9,166.6. 

60,000    TEN- 
SILE 
STRENGTH  . 

1-6,  10,000. 

65,000    TEN- 
SILE 
STRENGTH. 

1-6,  10,833.3. 

70,000    TEN- 
SILE 
STRENGTH. 

1-6,  11,666.6. 

jj 

It 

3 

1 

1 

11 

o  o 
n3 

S3  -3 

h 

i 

*i 

a.  fl 

B 

;* 

o 

1 

£ 

b 

OH 

|1 

00 

+3 

§5* 

6 

1 
1 

11 

81 

ii 
? 

a5 

I 

a 

IH 

ft 

fl'l 
8| 

B»3 

o- 

36 
Inches. 

.1875 
.21 
.23 
.25 
.26 
.29 
.3125 
.33 
.35 
.375 

78.12 
87.5 
95.83 
104.16 
108.33 
120.83 
130.2 
137.5 
145  83 
156.25 

93.74 
105. 
114.  99 
124.99 
129.99 
144.99 
156.24 
165. 
174.99 
187.5 

86.8 
97.21 
106.47 
115.74 
120.37 
134.25 
144.67 
15^.77 
162.03 
173.61 

104.16 
116.65 
127.76 
138.88 
144.44 
161  .11 
173.6 
183.32 
194  .43 
208.33 

95.48 
106.94 
117.12 
127.31 
132.4 
147.68 
159.14 
168.05 
178.23 
190.97 

114.57 
128.3 
140.54 
152.77 
158.  8b 
177.21 
190.96 
201.66 
213.87 
229  16 

104.16 
116.66 
127.77 
138.88 
144.44 
161.11 
173.6 
183.33 
194.44 
208.33 

124.99 
139.99 
153.32 
166.65 
173.32 
193.33 
208.32 
219.99 
233.32 
249.99 

112.84 
126.38 
138.41 
150.46 
156.48 
174.53 
188.07 
198.61 
210.64 
225.69 

135.4 
151.65 
166.  09 
180.55 
187.77 
209.43 
225.68 
238.33 
252.76 
271.82 

121.52 
136.11 
149.07 
162.03 
168.51 
187.90 
202.5 
213.88 
226  .84 
243.05 

145.82 
163.33 
178.88 
1SJ3.43 
202.21 
225.48 
243.04 
256.65 
272.20 
291.66 

38 
Inches. 

.1875 
.21 
.23 
.25 
.26 
.29 
.3125 
.33 
.35 
.375 

74.01 
82.89 
90.78 
98.68 
102.63 
114.47 
123.35 
130.26 
138.15 
148. 

88.89 
99.46 
108.93 
118.41 
123.  15 
137.36 
148.02 
156.31 
165.78 
177.60 

82.23 
92.1 
100.87 
109.64 
114.03 
127.19 
137. 
144.73 
153.5 
164.73 

98.67 
110.52 
121.04 
131.56 
136.83 
152.62 
164.46 
173.67 
184.21 
197.67 

90.46 
101.31 
110.96 
120.61 
125.43 
139.91 
150.76 
159.2 
168.85 
180.81 

108.54 
121.57 
133.15 
144.73 
150.51 
167.89 
180.91 
191.04 
202.  t2 
217.09 

98.68 
110.52 

121.  or. 

131.57 
136.84 
152.63 
164  .47 
173.68 
184.21 
197.36 

118.41 
132.62 
145.26 
157  88 
J64.2 
183.15 
197.36 
208.41 
221.05 
236.83 

106.9 
119.73 
131.13 
142.54 
148.24 
165.35 
178.17 
188.15 
199.56 
213.81 

128.28 
143.67 
157.35 
171.04 
177.88 
198.42 
213.8 
225.78 
239.47 
256.57 

115.13 
128.93 
141.22 
153.5 
159.64 
178.06 
191.88 
202.62 
214.91 
230.26 

138.16 
154.71 
169.46 
184.20 
191.56 
213.67 
230.25 
243.14 
257.89 
276.31 

40 
Inches. 

.1875 
.21 
.23 
.25 
.26 
.29 
.3125 
.33 
.35 
.375 

70.31 
78.75 
86.25 
93.75 
97.5 
108.75 
117  18 
123.75 
131.25 
140  .62 

84.37 
94.50 
103.5 
112.5 
117. 
130.5 
140.61 
148.5 
157.5 
168.74 

78.12 
87.49 
95.83 
104.16 
108.33 
120.83 
130.2 
137.49 
145.83 
156.24 

93.74 
104  98 
114.99 
124.99 
129.99 
144.99 
156.24 
164.98 
174.99 
187  '48 

85.93 
96.24 
105.41 
114.58 
119.16 
132.91 
143.22 
151.24 
160.41 
171.87 

103.11 
115.48 
126.49 
137.49 
142.99 
159  .49 
171.86 
181.48 
192.49 
206.24 

93.75 
105. 
115. 
125. 
130. 
145. 
156.25 
165. 
175. 
187.5 

112.5 
126. 
138. 
150. 
156. 
174. 
187.45 
198. 
210. 
225. 

101.56 
113.74 
124.58 
135.41 
140.83 
157.08 
169.27 
178.74 
189.58 
203.12 

121.87 
136.48 
149.49 
162.49 
168.99 
188.49 
203.12 
214.48 
227.49 
243.74 

109.37  131.24 
122.  49!  146.  98 
134.16160.99 
145.83174.99 
151.66181.99 
169.  16  :  202.  99 
182.29218.74 
192.491230.98 
204.16244.99 
218.  74  J262.  48 

42 
Inches. 

.1875 
.21 
.23 
.25 
.26 
.29 
.3125 
.33 
.35 
.375 

66.96 
75. 
82.14 
89.28 
92.85 
103.57 
111.6 
117.85 
125. 
133.92 

80.35 
90. 
98.56 
107.13 
111.42 
124.28 
133.92 
141  .42 
150. 
160.7 

74.40 
83.32 
91.23 
99.2 
103.17 
115.07 
124. 
130.94 
138.88 
148.8 

89.28 
99.99 
109.51 
119.04 
123.8 
138.08 
148.8 
157.12 
166.65 
178.56 

81.84 
91.66 
100.39 
109.12 
113.49 
126.57 
136.4 
114.04 
152.77 
163.68 

98.20 
109.99 
120.46 
130.94 
136.18 
151.85 
163.68 
172.84 
183.32 
196.40 

89.28 
100. 
109.52 
119.04 
123.8 
138.09 
148.74 
157.14 
166.66 
178.57 

107.13    96.72 
120.      108.33 
131.42118.65 
142.84128.96 
148.  56  '134.12 
165.7  |149.6 
178.56161.2 
188.56170.23 
199.99  180.55 
214.28193.45 

116.06104.16:124.99 
129.  991116.  661139.  99 
142.  38  1127.77  153.  32 
154.75138.88  166.65 
160.94144.441173.32 
179.52  161.  11H93.33 
193.44J  173.  61  1208  23 
204.27il83.33219.99 
216.  66  194.  44  1233.  32 
232.14  208.33  249.99 

44 
Inches. 

.1875 
.21 
.23 
.25 
.26 
.29 
.3125 
.33 
.35 
.375 

63  92 
71.59 
78.4 
85.22 
88.63 
98.86 
106.53 
112.5 
119.31 
127.81 

76.7 
85.9 
94.08 
102  26 
106  35 
118.63 
127.83 
135. 
143.17 
153.37 

71.01 
79.54 
87.12 
94.69 
98.48 
109.84 
118.36 
124.99 
132.57 
142.04 

85.22 
95.44 
104.54 
113.62 
118.17 
131.80 
142.03 
149.98 
159.08 
170.44 

78.12 
87.49 
95.83 
104.16 
108.33 
120.83 
130  2 
137.49 
145.83 
156.24 

93.74 
104.98 
114.99 
124.99 
129.99 
144.99 
156.24 
164.98 
174.99 
187  .48 

85.22 
95.45 
104.54 
113.63 
118.18 
131.81 
142.04 
150. 
159.09 
170.45 

102.26|  92.32 
114.54103.4 
125.44113.25 
136.35123.1 
141.81  128.02 
158.17142.79 
170.44  153.88 
180.      ,162.49 

110.781  99.42  119.3 
124.08  111.  36|133.63 
135.9  1121  96  146.35 
147.  72  1132.56  159.07 
153.62:137.87  165.44 
171.33153.78184.53 
184.65  165.  71I198.85 
194.98174.99209.98 

190.9  !172.  341206.  8    185.6 
204.54'184.65  221.58,198.86 

222.72 
238.63 

126 


STEAM  MAKING;  OR,  BOILER  PRACTICE. 


TABLE  or  PRESSURES,  ETC.,  CONTINUED. 


Diameter  of  Boiler. 

1 

o 

1" 

1 

3 

.1875 
.21 
.23 
.25 
.26 
.29 
.3125 
.33 
.35 
.375 

45,000    TEN- 
SILE 
STRENGTH. 

1-6,  7,500. 

i  50,000    TEN- 
SILE 
STRENGTH. 

1-6,  8,333.3. 

55,000    TEN- 
SILE 
STRENGTH. 

1-6,  9,166.6. 

60,000    TEN- 
SILE 
STRENGTH. 

1-6,  10,000. 

65,000    TEN- 
SILE 
STRENGTH. 

1-6,  10,833.3. 

70,000     TEN- 
SILE 
STRENGTH. 

1-6,  11,666.6. 

aJ 

«'l 

8§ 
*£ 
Z% 

s* 

g 

!I 

2^ 

& 

6 
f 

Is 

0.0 

s* 

i 
co 

s'l 

0>  S 

°S 

C^  r^J 

§* 

jj 

I 

11 
"1 

g3 

0 

B'«' 

§P 

°.2 

-  ."£ 

5,1 
r 

46 

Inches. 

61.14'   73  36    67  93 

81.51 

74.72 

89.66 

81.51 

97.81 

88.31  105  97!  95.1 

114.12 

68.47 
75. 
81.51 
81.78 
94.56 
101.9 
107.6 
114.13 
122.28 

82.16 
90 
97.81 
101.73 
113.47 
122.28 
129.12 
136.95 
146.73 

76.08 
83.33 
90.57 
94.2 
105.07 
113.21 
119.56 
126.8 
135.86 

91.29 
100. 
108.68 
113.04 
126. 
135.86 
143.47 
152.16 
163.03 

83.69 
91.66 
99.63 
103.62 
115.57 
124.54 
131.52 
139.49 
149.  45 

100.42    91.3 
109.99  100. 
119.55108.69 
124.  34  i  113.  44 
138  '.68  126.09 
149.44  135.86 
157.82143.97 
167.38152.17 
179.34  163.04 

109.56 
120. 
130.42 
135  64 
151.3 
163.03 
172.16 
182.6 
195.64 

98.91118.69106.52  127.82 
108.33  129.  S  9  116.  66  139.99 
117.75141.3    126.8    152.16 
122.46146.95131.88ll58.25 
136.59163.92147.1    176.52 
147.19  176,62158.51190.21 
155.43  186.  51J167.  39|200.86 
164.85197.82177.53  213.03 
176.62j211.94  190  21  228.25 

48 
Inches. 

.1875 
.21 
.23 
.25 
.26 
.29 
.3125 
.33 
.35 
.375 

58.59 

70.30 

65.1 

78  12    71  61 

85  OM     78  12 

93  74 

84  63  101  55 

91.13 

109  35 

65.62 
71.87 
78.12 
81.25 
90.62 
97.65 
103.12 
109.37 
117.18 

.78.74 
86.24 
93.74 
97.50 
108.74 
117.18 
123.74 
131.24 
140.61 

72.91 
79.85 
86.8 
90.27 
100.69 
108.5 
114.58 
121.52 
130.2 

87.49 
95.82 
104.16 
108.32 
120.82 
130.2 
137.49 
145.82 
156.  24 

80.2      96.24 
87.84  105.4 
95.48114.57 
99.3    119.16 
110.76  132  91 
119.35  143.22 
126.04151-24 
133.67160.4 
143.22171.86 

87.49 
95.83 
104.16 
108.33 
120.83 
130.21 
137.5 
145.83 
156.25 

104.98 
114.99 
124.99 
129.99 
144.99 
156.25 
165. 
174.99 
187.50 

94.79 
103.81 
112.84 
117.36 
130.9 
141.05 
148.95 
157.98 
169.27 

113.74 
124.57 
135.4 
140.83 
157  08 
169.26 
178.74 
189.57 
203.12 

102.08122.49 
111.8  1133.16 
121.52145.82 
126.38  151.65 
140.97  169.16 
151.9  182.28 
160.41192.49 
170.13204.15 
182.29218.74 

54 
Inches. 

.1875 
21 
.23 
.25 
.26 
.29 
.3125 
.33 
.35 
.375 

52.08 
58.  3S 
63.88 
69.44 
72.22 

62.49 
69.99 
76.65 
83.32 
86  66 

57-87 
64.81 
70.98 
77.16 
80  24 

69  44 

77.77 
85.17 
92.59 
96.28 

63.65    76.38 
71.29    85.54 
78.08    93.69 
84.87;101.84 
88  271105.92 

69.441  82.44 
77.77    93.32 
85.18;102.21 
92.59111.10 
96  29  115.54 

75.23 
84.25 
92.28 
100.3 
104.31 

90.27 
101.1 
110.73 
120.36 
125.17 

81.01 
90.74 
99.38 
108.02 
112  44 

97.21 
108.88 
119.  25 
129.  62 
134.8 
150.36 
162.03 
171.10 
181.47 
194.43 

80.55 
86.8 
91.66 
97.22 
104.16 

96.66 
104.16 
109.99 
116  66 
124.99 

89.5 
96.44 
101.84 
108.02 
115.74 

107.40 
115.72 
122.22 
129.62 
138.88 

98.45:118.14 
106.09127.30 
112.03134.43 
118.82142.58 
127.31  152.77 

107  .41 
115.55 
122.22 
129.62 
138.88 

128  88 
138.66 
146.66 
155.54 
166.65 

116.35 
125.38 
132.4 
140,43 
150.46 

139.62125.3 
150.45135.03 
158  88(142.59 
168  51151.23 
180.55  162.03 

60 
Inches. 

.1875 
,21 
.23 
.25 
.26 
.29 
.3125 
.33 
.35 
.375 

46.87 
52.5 
57.5 
62.5 
65. 
72.5 
78.12 
82.5 
87.5 
93.75 

56.24 
63. 
69. 
75. 
76. 
87. 
93.74 
99. 
105. 
112.5 

52.08 
58.33 
63.88 
69.44 
72.22 
80.55 
86.8 
91.66 
97.22 
104.16 

62.49 
69,99 
76.65 
83.32 
86.66 
96.66 
104,16 
109.99 
116.66 
124.99 

57.29 
64.16 
70.27 
76.38 
79.44 
88.61 
95.48 
100.83 
106.94 
114.58 

68.74 
76.99 
84.32 
91.65 
95.32 
106.33 
114.57 
120.99 
128.32 
137.49 
• 

62.5 
69.99 
76.66 
83.33 
86.66 
96.66 
104.18 
109.99 
116.66 
125. 

75. 
84. 
91.99 
99.99 
103.99 
115.99 
124.99 
132. 
139.99 
150. 

67.7 
75.83 
83.05 
90.27 
93.88 
104.72 
112.95 
119.16 
126.38 
135.41 

81.24 
90.99 
99.66 
108.32 
112.65 
125.66 
135.54 
142.99 
151.65 
162.49 

72.  91  !  87.49 
81.66    97.99 
89.  44  1  107.  32 
97.22  116.66 
101.  11  121.  33 
112.77  135.32 
121.52145.82 
128.3-.Jl53.99 
136.11  163.33 
145.83175.99 

66 
Inches. 

.1875 
.21 
.23 
.25 
.26 
.29 
.3125 
.33 
.35 
.375 

42.61 
47.72 
52.27 
56.81 
59.09 
65.90 
71. 
75. 
79.56 
85.22 

51.13 
57.26 
62.72 
68.17 
70.9 
79.08 
85.2 
90. 
95.47 
102-26 

47.34 
53. 
58. 
63.13 
65.65 
73.23 
78.91 
83.33 
88.38 
94.69 

56.8 
63.63 
69.69 
75.75 
78.78 
87.87 
94.69 
99.99 
106.05 
113.62 

52.07 
58.33 
63.88 
69.44 
72.22 
80.55 
86.89 
91.66 
97.22 
104.16 

62.49 
69.99 
76.65 
83.32 
86.66 
96.66 
104.16 
109.99 
116.66 
124.99 

56.81 
63.63 
69.69 
75.75 
78.78 
87.87 
94.69 
99.99 
106. 
113.62 

68.17 
76.35 
83.62 
90.90 
94.53 
105.44 
113.62 
120. 
127.27 
136.34 

61.55 
68-93 
75.5 
82.07 
85.35 
95.2 
102.58 
108.33 
114.89 
123.1 

73.86 
82.71 
90.6 
98.48 
102.42 
114.24 
123.09 
129.99 
137.86 
147.72 

66.28 
74.24 
81.31 
88.37 
91.91 
102.52 
110.47 
116.66 
123.  73 
132.57 

79.53 
89.08 
97  57 
106.04 
110.29 
123.02 
132.56 
139.99 
148.47 
159.08 

.1875    39.06 
.21       43.75 
.23       47.91 

46.87!  43.4 
52.5      48.6 
57.49i  53.24 

52.08 
58.33 
63.88 

47.74 
53.47 
58.56 

57.28 
64.16 
70.27 

52.08 
58.33 
63.88 

62.49 
69.99 
76.65 

56.42 
63.19 
62.21 

67.70 
75.82 
83.05 

60.76 
68.05 
74.53 

72.91 
81.66 
89.43 

THE  DESIGN,  CONSTRUCTION,  ETC. 


127 


TABLE  OF  PRESSURES,  ETC.,  CONTINUED. 


45,000     TEN- 

50,000   TEN- 

55,000    TEN- 

60,000   TEN- 

65,000    TEN- 

70,000   TEN- 

SILE 

SILE 

SILE 

SILE 

SILE 

SILE 

I 

CO 

B 

STRENGTH. 

STRENGTH. 

STRENGTH. 

STRENGTH  . 

STRENGTH. 

SIRENGTH. 

'o 

| 

E 

1-6,  7,500. 

1-6,  8,333.3. 

1-6,  9,166.6. 

1-6,  10,000. 

1-6,  10,833.3. 

1-6,  11,666.6. 

eter  of  B 

:ness  of  ! 

i 

sr  cent, 
itional. 

i 

r  cent, 
itional. 

jj 

f| 

i 

SI 

1 

i 

33 

3 

fig 

g 

3 

1 

&s 

1 

PITS 

1 

ftS 

GO 

QJ  73 

ft  73 

CO 

ftS 

03             0.2 

1 

01 

a 

ci 

• 

6 

9 

B 

3 

Q)                                     M 

s 

H 

£ 

& 

§3 

£ 

8 

£ 

S 

AH 

§ 

PH      i    §» 

.25 

52.08 

62.49 

57.87 

69.44 

63.65 

76.38 

69.44 

83.32 

75.22 

90.26 

81.01 

97.21 

72 

.26 

54.16 

64.99 

60.18 

72.21 

66.2 

79.44 

72.22 

86.66 

78.24 

93.88 

84.25 

101.10 

Inches. 

.29 

60.41 

72.49 

67.12 

80.54 

73.84 

88.60 

80.55 

S6.66 

87.26104.71 

93.98 

112.77 

.3125 

65.10 

78  12 

72.33 

86.8 

79.57 

95.48 

86.8 

104.16 

94.03 

112.83 

101.27 

121.52 

.33 

68.75 

82.5 

76.38 

91.65 

84.02 

100.82 

91.66 

109.99J  99.3 

119.16 

106.94 

128.32 

.35 

72.91 

87.49 

81.01 

97.21 

89.11 

106.93 

97.22 

116.66 

105.32 

126.38 

113.42 

136.1 

.375 

78.12 

93.74 

86.8 

104  16 

95.48 

114.57 

104  .  16 

124.99 

112.84135.43 

121.52 

145.82 

.1875 

36.05 

43.21 

40.06 

48.07 

44.07 

52.87 

48.07 

57.68 

52.08 

62.49 

56.08 

67.29 

.21 

40.38 

48.45 

44.87 

53.84 

49.35 

59.22 

53.84 

64.60 

58.33 

69.99 

62.82 

75.38 

.23 

44.23 

53.07 

49.14 

58.96    54.05 

64.86 

58.95 

70.76 

63.88    76.65 

68.80 

82.56 

.25 

48.07 

57.68 

53.41 

64.09    58.76 

70.5 

64.4 

76.92 

69.44    83.32 

74.78 

89.73 

78 

.26 

50. 

60. 

55.55 

66.66 

66.11 

73.33 

66.66 

79.99 

72.22    86.66 

77.77 

93.32 

Inches. 

.29 

55.76 

66.91 

61.96 

74.35 

68.16 

81.79 

74.35 

89.22 

80.55    96.66 

86.75 

104.1 

.3125 

60.09 

72.1 

66.77 

80.12 

73.45 

88.14 

80.12 

96.14 

86.8  I  104.  16 

93.48 

112.17 

.33 

63.46 

76.15 

70.51 

84.61    77.56 

93.07 

84.61 

101.53 

91.66  109.99 

98.71118.45 

.35 

67.3 

80.76 

74.78 

89.73 

82.26 

98.71 

89.74 

107.68 

97.22J116.66 

104.70  125.64 

.375 

72  11 

86.53 

80.12 

96.14 

88.14 

105.76 

96.15 

115.38 

104.16124.99 

112.17 

134.6 

.1875 

33.48 

40.17 

37.2 

44.68 

40.92 

49.1 

44.64 

53.56 

48  36 

58.03 

52.08 

62.49 

.21 

37.5 

45. 

41.66 

49.99 

45.83 

54.99 

50. 

60. 

54.16 

64.99 

58.33J  69.99 

.23 

41.02 

49.22 

45.63 

54.75 

50.19 

60.22 

54.75 

65.71 

59.32 

71.18 

63.65    76.38 

.25 

44.64 

53.56 

49.6 

59.52 

54.56 

05.47    59  52 

71.42 

64.48 

77.37 

69.44    83.32 

84 

.26 

46.42 

55.7 

51.58 

61.89 

56.74 

68.08    61.9 

74.28 

67.05 

HO.  46 

72.221  86.66 

Inches. 

.29 

51.78 

62.13 

57.53 

69.03 

63.29 

75.94    69.04 

82.84 

74.8 

89.76 

80.55 

96.66 

.3125 

55.8 

66.96 

62. 

74.4 

68.2 

81.84'  74.4 

89.28 

80.6 

96.72 

86.8 

104.16 

.33 

58.92 

70.7 

65  .47 

78.56 

72.02 

86.42    78.57 

94.28 

85.11 

102.13!  91.66 

109.99 

.35 

62.5 

75- 

69.44 

83.32 

76.38 

91.65'  83.33 

99.99 

90.27108.321  97.22116.66 

.375 

66.96 

80.35 

74.4 

89.28 

81.84 

98.2  |  89.28 

107.13 

96.72116.06 

104.16 

124.99 

.1875 

31.25 

37.5 

34.72 

41.66 

38.19 

45.82;  41.66 

49.99|  45.13;  54.15 

48.68 

58.33 

.21 

35. 

42. 

38.88 

46.65 

42.77 

51.  321  46.66 

55.99 

50.55'  60.66 

54.44 

65.32 

.23 

38.33 

45.99 

42.59 

51.10 

46.85 

56.  22'  51.11 

61.33 

55.37    66.44 

59.62 

71  54 

.25 

41.66 

49.99 

46.29 

55.54 

50.92 

6i.l   !  55.55 

66.66 

60.18    72.21 

64.81 

77.77 

90 

.26 

43.33 

51.99 

48.14 

57.76 

52.96 

63.55;  57.77 

69.32    62.59    75.1 

67.4 

80.88 

Inches. 

.29 

48.33 

57.99 

53.7 

64.44 

59.07 

70.8  !  64.44 

77.32    69.81    83.77 

75.18 

90.21 

.3125 

52.08 

62.49 

57.86 

69.43 

63.65 

76.38    69.44 

83.32    75.23|  90.27 

81.01    97.21 

.33 

55. 

66. 

61.11 

73.33 

67.22 

80.66i  73.33 

87.991  79.44 

95.32 

85.55 

102.66 

.35 

58.33 

69.99 

64.81 

77.77 

71.29 

85.54;  77.77 

93.32    84  25 

101  1 

90.72 

108.88 

.375 

62.5 

75. 

69.44 

83.32 

76.38 

91.65 

83.33 

99.99    90.27 

108.32 

97.22 

116.66 

.1875 

29.29 

35.14 

32.55 

39.06 

35.8 

42.96 

39.06 

46.87 

42.31 

50.77 

45.57 

54.68 

.21 

32.81 

39.37 

36.45 

43.74 

40.1 

48.12 

43.75 

52.5 

47.39 

56.86 

51.04 

61.24 

.23 

35.93 

43.11 

39.93 

47.91 

43.92 

52.7     47.91 

57.49    51.9 

62.28 

55.9 

67.08 

.25 

39.06 

46.87 

43.4 

52.08 

47.74 

57.28 

52.08 

62.491  56.42 

67.67 

60.76 

72.91 

96 

.26 

40.62 

48.74 

45.14 

54.16 

49.65 

59.58 

54.16 

64.99!  58.78 

70.53 

63.19 

75.82 

Inches. 

.29 

45.31 

54.37 

50.34 

60.4 

55.38 

66.45 

60.41 

72.49;  65,45 

78.54|   70.48 

84.57 

.3125 

48.82 

58.58 

54.25 

65.1 

59.67 

71.6      65.1 

78.12    70.52 

84.62    75.95 

91.14 

.33 

51.56    61.87 

57.29 

68.74 

63.02 

75.62    68.75 

82.5      74.47 

89.36    80.2 

96.24 

.35 

54.6*    65.61 

60.76 

72.91 

66.83 

80.19 

72.911  87.49 

78.99 

94.781  85.06 

102.07 

.375 

58.58!  70.29 

65.1      78.12 

71.61 

85.93 

78.12!  93.74 

84.63 

101.551  91.14 

109.6 

128 


STEAM  MAKING;  OR,  BOILER  PRACTICE. 


TABLE    OF    PRESSURES 

Allowed  under  the  Provisions  of  the  Special  Act  of  Congress  relating  to  the  Limitation 
of  Steam  Pressure  of  Vessels  used  Exclusively  for  Towing  and  Carrying  Freight  on 
the  Mississippi  River  and  its  Tributaries.  Approved  January  6,  1874. 


-tp  saqom  09 


-ip  saqom  ss 


IP  saqom  93 


-IP  saqoin  f  s 


-IP  saqom  ss 


S»ft      as      co      t- 
O         O         —I         rH 


S    S    S    S    S 


g 

8    3 


r-l         r-l         d 


3    S 


3    §    S 


-ip  saqom  OS 


g    3    8    S    §          S 
g    g    S    S    8    S    S 


S    2    g 


-IP  saqom  8f 


-IP  saqom  9^ 


-IP  saqom  ^ 


• ja laraB 
•IP  saqoui  ct 


-IP  saqom  of 


-IP  saqom  88 


-IP  saqom  98 


-IP  saqom  ?e 


§    S    S    8 


5!     5     S 


5    S    S 


3    S 


IS    §    S    55 


F^QO-^1OO^Ht-'-^'OOl^<OOTHt* 

3s    3§^Srt«rtrtrt5Hrt5 


s  §s 


§000000 
S     S     5     oo     IH      •* 


3§ 


s  s  s  s 

—         —         —         — 


S    3 


^  o'      oo 

J2   3 


3    S    5    §8 


•UOJt  JO 


•g" 

a 


The  above  table  gives  the  steam-pressure  allowed  on  boilers  used  on  freight  and  tow- 
ing steamers,  the  standard  pressure  being  150  pounds  for  a  boiler  42  inches  diameter, 
and  .25  of  an  inch  thick.  To  find  the  pressure  required  on  other  size  boilers,  (not  given 
in  the  above  table,)  multiply  12,600  by  the  thickness  and  divide  by  the  radius,  or  half  the 
diameter. 


THE  DESIGN,  CONSTRUCTION,  ETC.      * 


129 


TREASURY  DEPARTMENT, 

Document 
Steamboat  Inspecti 


PARTMENT,  ) 
No.  57.  [• 
ispection.  } 


RULES  AND   REGULATIONS   RELATING  TO  PRESSURES,  BOILERS,  AND  THE 
INSPECTION  OF  BOILER-PLATES. 

KTJLE  1. 

Pressure  Allowable  on  Boilers  of  Various  Dimensions,  Built  Prior  to  Feb.  2S,  1872. 
(Pressure  Equivalent  to  the  Standard  Pressure  for  a  42-inch  Boiler,  M-inch  Iron.) 


<H 

£ 

d 

a 

d 

d 

d 

d 

GO 

g| 

05  (3 

CO   (3 

03  *' 

03    ^ 

a  qj 

!H' 

WIRE-GAUGE. 

<u 

Id 

«a 

fa 

§1 

rj    Q) 

Is 

«! 

B| 

"§  d 

d  § 

sa 

"*% 

S 

•3 

EH 

« 

co 

§§ 

9 

5! 

3 

Inch. 

Lbs. 

Lbs. 

Lbs. 

Lbs. 

Lbs. 

Lbs. 

Lbs. 

1 

5—16 

169  85 

160  41 

151  97 

144.37 

137.50 

131  25 

125  54 

2     ... 

14—48 

158  52 

149  72 

141  84 

134.75 

128.33 

122  50 

117  17 

3  

13—48 

147.20 

139.03 

131.76 

125.12 

119.16 

113.75 

108.80 

A. 

1—4 

135  88 

128  33 

121.57 

115  50 

110.00 

105  00 

100  43 

g  

11—48 

124  55 

117.63 

111.44 

105.87 

100.83 

96.25 

92.06 

6  

10—48 

113.23 

106.94 

101.31 

96.25 

91.66 

87.50 

83.69 

7  

3—16 

101  .91 

96.24 

91.18 

86.62 

82.50 

78.75 

75.32 

Boilers,  however,  built  of  steel  plates  prior  to  Feb.  28,  1872,  shall  be 
deemed  to  have  a  tensile  strength  of  75,000  pounds  to  the  sectional  square 
inch,  whether  stamped  or  not,  and  shall  be  tested  under  the  rule  pre- 
scribed for  boilers  inspected  under  the  provisions  of  section  36  of  the  act 
relating  to  boilers,  built  after  the  28th  of  February,  1872. 

TABLE    OF    PRESSURES   ALLOWABLE    ON    BOILERS   MADE    SINCE 
FEBRUARY    28,    1872. 

KULE  2.  In  the  first  column  to  the  left  will  be  found  the  diameter  of 
boilers  varying  by  2"  from  36"  to  48",  and  by  6"  from  48"  to  96".  In  the 
second  column  will  be  found  the  thickness  of  boiler-plates,  expressed  in 
the  decimal  parts  of  an  inch,  and  varying — by  r^o"  nearly — from  ps"  to  |"; 
.1875,  .25,  .3125,  and  .375  are  the  decimal  equivalents  for  -&",  |",  &",  and 
§".  The  decimals,  .21,  .23,  .26  and  .29  correspond  nearly  to  £§",  ^',  \%" , 
and  i|"  in  the  table  of  the  pressures  allowable  on  boilers  made  prior  to 
Feb.  28,  1872.  At  the  heads  of  the  double  columns  will  be  found  the  ten- 
sile strength  of  the  plates  per  square  inch  of  section;  also  &  of  that  amount. 
The  pressures  allowable  on  single -riveted  boilers  will  be  found  in  the  first 
divisions  of  the  double  columns  under  the  tensile  strengths  and  opposite 
the  diameters  and  thicknesses;  and  in  the  second  divisions,  the  pressures 
allowable  on  boilers  where  all  the  rivet-holes  have  been  fairly  drilled  in- 


130  STEAM  MAKING;  OR,  BOILER  PRACTICE. 

stead  of  punched,  and  the  longitudinal  laps  of  their  cylindrical  parts 
double-rivetted.  in  the  manner  prescribed  by  law. 

The  pressure  for  any  dimension  of  boilers  not  found  in  the  above 
table,  can  be  ascertained  by  the  following  rule,  viz: 

Multiply  one-sixth  (£)  of  the  lowest  tensile  strength  found  stamped  on 
any  plate  in  the  cylindrical  shell  by  the  thickness — expressed  in  inches  or 
parts  of  an  inch— of  the  thinnest  plate  in  the  same  cylindrical  shell,  and 
divide  by  the  radius  or  half  diameter — also  expressed  in  inches — and  the 
sum  will  be  the  pressure  allowable  per  square  inch  of  surface  for  single- 
rivetting,  to  which  add  20  per  centum  for  double-rivetting,  etc. 

The  hydrostatic  pressure  applied,  under  the  above  table  and  rule, 
must  be  in  the  proportion  of  150  pounds  to  the  square  inch  to  100  pounds 
to  the  square  inch  of  the  working  pressure  allowed. 

Where  flat  surfaces  exist,  the  inspector  must  satisfy  himself  that  the 
bracing  and  all  other  parts  of  the  boiler  are  of  equal  strength  with  the 
shell,  and  he  must  also,  after  applying  the  hydrostatic  test,  thoroughly 
examine  every  part  of  the  boiler  to  see  that  no  weakness  or  fracture  has 
been  caused  thereby.  Inspectors  must  see  that  the  flues  are  of  proper 
thickness  to  avoid  the  danger  of  collapse.  Flues  of  16  inches  in  diameter, 
made  after  July  1,  1877,  must  not  be  less  than  ,Btf  of  an  inch  in  thickness, 
and  in  proportion  for  flues  of  a  greater  or  less  diameter. 

RULE  3.  Every  iron  or  steel  plate  intended  for  the  construction  of 
boilers  to  be  used  on  steam  vessels  shall  be  stamped  by  the  manufacturer 
in  the  following  manner,  viz.,  at  the  diagonal  corners,  at  a  distance  of 
about  4  inches  from  the  edges,  and  also  at  or  near  the  centre  of  the  plate, 
with  the  name  of  the  manufacturer,  the  place  where  manufactured,  and 
the  number  of  pounds  tensile  strain  it  will  bear  to  the  sectional  square 
inch. 

When  a  sheet  of  boiler  iron  is  found  by  the  inspector  with  one  or  more 
stamps  upon  the  same,  the  inspectors  shall  in  every  such  case  be  governed, 
and  rate  the  tensile  strength  of  iron  in  accordance  with  the  lowest  stamp 
found  upon  the  same. 

i  RULE  4.  The  manner  of  inspecting  and  testing  boiler  plates  intended 
to  be  used  in  the  construction  of  marine  boilers,  by  the  United  States  in- 
spectors, shall  be  as  follows,  viz: 

The  inspectors  shall  visit  places  where  marine  boilers  are  being  con- 
structed, as  often  as  possible,  for  the  purpose  of  ascertaining  and  making 
a  record  of  the  stamps  upon  the  material,  its  thickness,  and  other  qualities. 
To  ascertain  the  tensile  strain  of  the  plates  the  inspectors  shall  cause  a 
piece  to  be  taken  from  each  sheet  to  be  tested,  the  area  of  which  shall 
equal  one-quarter  of  one  square  inch,  on  all  iron  ^  of  an  inch  thick,  and 
under;  and  on  all  iron  over  fy  of  an  inch  thick  the  area  shall  equal  the 
square  of  its  thickness;  and  the  force  at  which  the  piece  can  be  parted  in 
the  direction  of  the  fibre  or  grain,  represented  in  pounds  avoirdupois — 
the  former  multiplied  by  four,  the  latter  in  proportion  to  the  ratio  of  its 
area — shall  be  deemed  the  tensile  strain  per  square  inch  of  the  plate  from 
which  the  sample  was  taken;  and  should  the  tensile  strength  ascertained 


THE  DESIGN,  CONSTRUCTION,  ETC.    '  131 

by  the  test  equal  that  marked  on  the  plates  from  which  the  test  pieces 
were  taken,  the  said  plates  must  be  allowed  to  be  used  in  the  construction 
of  marine  boilers;  provided  always  that  the  said  plates  possess  the  other 
qualities  required  by  law,  viz.,  homogeneousness,  toughness,  and  ability 
to  withstand  the  effect  of  repeated  heating  and  cooling;  but  should  these 
tests  prove  the  marks  on  the  said  plates  to  be  overstamped,  the  lots  from 
which  the  test  plates  were  taken  must  be  rejected  as  failing  to  have  the 
strength  stamped  thereon.  But  nothing  herein  shall  be  so  construed  as  to 
prevent  the  manufacturers  from  restamping  such  iron  at  the  lowest  tensile 
strain  indicated  by  the  samples,  provided  such  restamping  is  done  previ- 
ous to  the  use  of  the  plates  in  the  manufacture  of  marine  boilers. 

To  ascertain  the  ductility  and  other  lawful  qualities:  iron  of  45,000 
pounds  tensile  strength,  and  under,  shall  show  a  contraction  of  area  of  15 
per  cent.,  and  each  additional  1,000  pounds  tensile  strength  shall  show  1 
per  cent,  additional  contraction  of  area,  up  to  and  including  55,000  T.  S. 

In  the  following  table  will  be  found  the  widths— expressed  in  hun- 
dredths  of  an  inch — that  will  equal  one-quarter  of  one  square  inch  of  sec- 
tion, of  the  various  thicknesses  of  boiler  plates.  The  signs  +  (plus)  and 
—  (minus)  indicate  that  the  numbers  against  which  the  signs  are  placed 
are  a  trifle  more  or  less,  but  will  not,  in  any  instance  exceed  f^  of  an 
inch. 

The  gauge  to  be  employed  by  inspectors  and  others,  to  determine  the 
thickness  of  boiler-plates,  and  the  widths  in  the  table,  will  be  any  stand- 
ard American  gauge  furnished  by  the  Treasury  Department. 

•&"  =  133  -  .26  =  96  -  .35  =  71  - 

.21    =  119  -  .29  =  86  -  f'=  67  -f 

.23    =  109  +  tV'=  80  &"=  57  - 

\"  =  100  .33  =  76  +  V'=  50 


•  ^  *, 

f 

D 

c 

Jones  &  Co.,Pittsburgh,Pa.,60.000  tensile  strength 

1 

1 

Q 

All  samples  intended  to  be  tested  on  the  Eiehle,  Fairbanks,  or  other 
reliable  testing  machine,  must  be  prepared  in  form,  according  to  the  above 
diagram,  viz.,  8  inches  in  length,  2  inches  in  width,  cut  out  at  their  centres 
in  the  manner  indicated. 


132 


STEAM  MAKING;  OR,  BOILER  PRACTICE. 


RULE  5.  The  hulls  and  boilers  of  all  tug,  towing,  and  freight-boats 
shall  be  inspected  in  accordance  with  section  59  (section  4427,  Revised 
Statutes  of  the  act  aforesaid,  but  steam  registering  gauges  shall  not  be 
required  on  the  above-named  steamers. 

RULE  6.  The  feed  water  shall  not  be  admitted  into  any  boiler,  on 
board  of  any  steam  vessel  subject  to  the  jurisdiction  of  this  board,  at  less 
temperature  than  one  hundred  (100)  degrees  Fahr.  for  low-pressure  or 
condensing  boilers,  and  one  hundred  and  eighty  (180)  degrees  Fahr.  for 
high  pressure  or  non-condensing  boilers;  nor  shall  cold  water  be  admitted 
into  any  such  boilers  while  the  water  is  at  a  less  temperature  than  the 
surrounding  atmosphere. 

All  tests  made  of  boiler  material  must  be  recorded  upon  a  table  of  the 
following  form: 

TENSILE  TESTS  OF  SAMPLES  OF  MATERIAL  INTENDED  TO  BE  EMPLOYED 
IN  THE  CONSTRUCTION  OF  BOILERS  OF  STEAM  VESSELS  MADE  ON 
TESTING  MACHINE. 


o5 

4)  g 

00  OJ-H     . 

.<_ 

-o       '  « 

, 

& 

05  O 

<2    *S  5 

CD 

C?  ^H 

• 

P, 

<D 

£. 

IIP 

(J 

I'2           * 

s 

1 

9? 

Date  when  tests  wer 

From  whom  sample 
obtained,  and  by 
tested. 

Material,  iron  or  stee 

Stamp  or  label  on 
which  must  be  the 
stamps  on  the  i 
from  which  they  ar 

Thickness  of  samp] 
pressed  in  hundre 
an  inch. 

Width  of  samples,  ex 
in  hundredths  of  a 

Strain  at  which  each 
parted. 

Strain  per  square  incl 
tion. 

Reduced  thickness. 

Reduced  width. 

Contraction  of  are 
cent. 

REMARKS. 

RULE  7.  Whenever  steamers  use  a  pressure  upon  their  boilers  ex- 
ceeding 60  pounds  to  the  square  inch,  they  shall  be  inspected  as  high- 
pressure  steamers  and  designated  as  such. 

RULE.  8.  Inspectors  shall  not  allow  the  use  of  vertical  tubular  boilers, 
on  waters  flowing  into  the  Gulf  of  Mexico,  unless  the  water  line  of  the 
boiler  is  the  lawful  distance  above  the  upper  end  of  tubes  and  fire  line. 

RULE  9.  Stand  pipes  used  on  high  pressure  Western  river  steamers 
shall  be  constructed  of  iron,  tested  and  stamped  as  required  by  law;  but 
when  a  steamer  is  to  be  navigated  in  salt  waters,  and,  in  the  opinion  of  the 
supervising  inspector,  cast  iron  may  be  employed  with  greater  safety,  he 
may  allow  stand  pipes  constructed  of  cast  iron  to  be  used  on  steamers  of 
the  latter  class. 


THE  DESIGN,  CONSTIi UCT10N,  ET< '.  1 33 

KULE  10.  All  steamers  hereafter  constructed,  navigating  the  ocean, 
sounds,  lakes,  bays,  and  rivers,  and  subject  to  the  jurisdiction  of  the 
board,  shall  have  a  clear  space  of  not  less  than  16  inches  on  all  sides  of 
the  boilers,  and  at  the  back  end  of  all  such  boilers  there  shall  be  a  clear 
space  of  2  feet.  Slip-joints  in  steam  pipes  shall,  in  their  working  parts, 
when  the  steamer  is  to  be  employed  in  navigating  salt  water,  be  made  of 
copper  or  composition. 

All  boilers  hereafter  built  shall  have  a  plate  or  plates  of  sufficient  size 
fastened  on  the  boiler  on  which  shall  be  the  name  of  the  manufacturer, 
the  place  where  manufactured,  and  the  tensile  strength  of  the  iron,  and 
also  the  name  of  the  builder  of  the  boiler,  where  built,  and  the  year. 


RELATING  TO  INSTRUMENTS. 


KULE  33.  All  steam  registers  shall  be  so  constructed  as  to  be  operated 
wholly  by  the  pressure  of  steam  in  the  boilers,  to  which  said  steam  regis- 
ters are  attached;  and  their  mechanism  shall  be  enclosed  in  a  metal  case, 
so  arranged  as  to  preclude  the  possibility  of  its  being  interfered  with  from 
the  outside,  and  be  secured  by  a  lock  or  such  other  device  as  the  Board  of 
Supervising  Inspectors  and  the  Secretary  of  the  Treasury  shall  approve; 
said  steam  registers  shall  be  provided  with  a  suitable  stop  cock  to  shut  off 
the  steam  from  the  register  in  case  of  necessity,  and  such  stop  cock  shall 
be  so  placed  and  arranged  as  to  be  secured  or  locked  by  the  same  device 
or  lock  employed  to  secure  the  register  from  the  interference  of  unauthor- 
ized persons.  The  front  or  face  of  all  registers  shall  be  of  heavy  glass,  to 
enable  passengers  and  others  to  observe  at  all  times  the  pressure  of  steam. 
The  number  of  times  the  working  pressure  allowed  has  been  exceeded, 
and  the  highest  point  attained,  may  be  registered  either  upon  a  continu- 
ous strip  of  paper  under  a  pencil  moved  by  the  variations  in  the  pressure 
of  steam,  or  by  hands  or  pointers  moving  over  a  dial  plate  or  plates,  ar- 
ranged and  graduated  for  that  purpose. 

All  steam  registers  shall  be  so  constructed  as  to  record  each  excess  of 
more  than  2^  pounds  above  the  working  pressure  allowed  for  low-pressure 
boilers,  and  of  more  than  5  pounds  above  the  working  pressure  allowed 
for  high-pressure  boilers.  And  each  steam  register,  attached  to  either 
high  or  low-pressure  boilers,  shall  be  capable  of  recording  at  least  10 
pounds  above  the  test  pressure.  All  steam  registers  shall  be  placed  in  a 
conspicuous  position,  under  the  direction  of  the  inspectors,  who  shall  also 
prescribe  the  manner  in  which  steam  registers  shall  be  attached  to 
boilers. 

It  shall  be  the  duty  of  all  inspectors,  before  issuing  a  certificate  of  in- 
spection to  any  steamer,  to  ascertain,  by  actual  test,  that  the  steam  regis- 
ter required  by  law  is  in  accordance  with  the  foregoing  rules  approved  by 
the  Board  of  Supervising  Inspectors  and  by  the  Seeretary  of  the  Treasury. 
The  makers  and  sellers  of  steam  registering  gauges  shall  furnish  to  the 


134  STEAM  MAKING;  OR,  BOILER  PRACTICE. 

purchaser  an  acceptable  guarantee  that  the  same  will  work  correctly,  and 
according  to  the  law  and  rule,  one  year. 

BULE  34.  All  steamers  shall  have  inserted  in  their  boilers  plugs  of 
Banca  tin,  at  least  ^-inch  in  diameter  at  the  smallest  end  of  the  internal 
opening,  in  the  following  manner,  to- wit:  Cylinder  boilers  with  flues 
shall  have  one  plug  inserted  in  one  flue  of  each  boiler;  and  also  one  plug 
inserted  in  the  shell  of  each  boiler  from  the  inside,  immediately  before 
the  fire  line,  and  not  less  than  4  feet  from  the  forward  end  of  the  boilers. 
All  fire  box  boilers  shall  have  one  plug  inserted  in  the  crown  of  the  back 
connection,  or  in  the  highest  fire  surface  of  the  boiler.  These  plugs,  in 
external  diameter,  must  correspond  in  size  to  a  1-inch  gas  or  steam  pipe 
screw  tap. 

RULE  35.  All  steamers  having  one  or  two  boilers  shall  have  three 
suitable  gauge  cocks  in  each  boiler.  Those  having  three  or  more  boilers 
in  battery  shall  have  three  in  each  outside  boiler  and  two  in  each  remain- 
ing boiler  in  the  battery;  and  the  middle  gauge  cocks  in  all  boilers  shall 
not  be  less  than  4  inches  above  the  top  of  the  flues,  tubes,  or  crown  of  the 
fire-box. 

KULE  36.  Safety  valves  to  be  attached  to  boilers,  intended  for  steam 
vessels  built  six  months  after  the  approval  of  this  rule,  shall  have  an  area 
of  not  less  than  1  square  inch  to  2  square  feet  of  the  grate  surface,  when 
the  common  safety  valve  is  employed. 

But  when  safety  valves  are  to  be  used,  the  lift  of  which  will  give  an 
effective  area  of  one-half  of  that  due  the  diameter  of  the  valve,  the  area 
required  shall  not  be  less  than  one-half  of  1  square  inch  to  2  square  feet 
of  the  grate  surface. 

The  valves  shall  be  so  arranged  that  each  boiler  on  the  steam  vessel 
shall  have  one  separate  safety  valve,  unless  the  arrangement  is  such  as  to 
preclude  the  possibility  of  shutting  off  the  communication  of  any  boiler 
with  the  safety  valve  or  valves  employed.  This  arrangement  shall  also 
apply  to  the  lock-up  safety  valves  when  they  are  employed. 

The  lock-up  safety  valves  shall  be  such  as  are  approved  by  the  Board 
of  Supervising  Inspectors,  and  of  such  dimensions  as  the  inspectors  may 
deem  necessary. 

The  term  effective  area  employed  in  this  rule  has  reference  to  the 
opening  obtained  by  the  lift. 

The  first  section  of  this  rule  applies  to  valves  constructed  in  material, 
workmanship,  and  principle,  according  to  the  drawings  for  a  safety  valve 
printed  with  these  rules,  and  all  common  lever  safety  valves  to  be  here- 
er  applied  to  the  boilers  of  steam  vessels  must  be  so  constructed. 

When  this  construction  of  a  safety  valve  is  applied  to  the  boilers  of 
steamers  navigating  rough  waters,  the  link  may  be  connected  direct  with 
the  spindle  of  the  valve;  provided  always,  that  the  fulcrum  or  points  upon 
which  the  lever  rests  are  made  of  steel,  knife  or  sharp- edged,  and  hard- 
ened; in  this  case  the  short  end  of  the  lever  should  be  attached  directly  to 
the  valve-casing.  In  all  cases  the  link  requires  but  a  slight  movement, 
not  exceeding  |  of  an  inch. 


THE  DESIGN,  CONSTRUCTION,  ETC. 


Keferring  to  the  report  on  safety  valve  tests,  conducted  under  the  au- 
thority of  the  Board  of  Supervisors,  the  construction  of  valves  which  will 
apply  to  the  second  section  of  this  rule  is  described. 

All  the  points  of  bearing  on  lever  must  be  in  the  same  plane. 

The  distance  of  the  fulcrum  must  in  no  case  be  less  than  the  diameter 
of  the  valve- opening. 

The  length  of  the  lever  should  not  exceed  the  distance  of  the  fulcrum 
multiplied  by  10. 

The  width  of  the  bearings  of  the  fulcrum  must  not  be  less  than  three- 
fourths  (|)  of  one  inch. 

The  length  of  the  fuicrum  link  should  not  be  less  than  four  (4)  inches. 

The  lever  and  fulcrum  link  must  be  made  of  wrought- iron  or  steel, 
and  the  knife- edged  fulcrum  points  and  bearings  for  the  points  must  be 
made  of  steel  and  hardened. 

The  valve,  valve  seat,  and  bushings  for  the  stem  or  spindle  must  be 
made  of  composition  (gun  metal)  when  the  valve  is  intended  to  be  at- 
tached to  a  boiler  using  salt  water;  but  when  the  valve  is  to  be  attached 
to  a  boiler  using  fresh  water,  and  generating  steam  of  a  high  pressure,  the 
parts  named,  with  the  exception  of  the  bushings  for  the  spindle,  may  be 
made  of  cast  iron. 

The  valve  must  be  guided  by  its  spindle,  both  above  and  below  the 
ground  seat  and  above  the  lever,  through  supports  either  made  of  compo- 
sition (gun  metal)  or  bushed  with  it. 

The  spindle  should  fit  loosely  in  the  bearings  or  supports. 

When  the  valve  is  intended  to  be  applied  to  the  boilers  of  steamers 
navigating  rough  waters,  the  fulcrum  link  may  be  connected  directly  with 
the  spindle  of  the  valve;  providing  always  that  the  knife- edged  fulcrum 
points  are  made  of  steel  and  hardened,  and  that  the  object  .sought  by  the 
link  is  obtained,  viz.,  the  vertical  movement  of  the  valve  unobstructed  by 
any  lateral  movement. 

In  all  cases  the  weight  must  be  adjusted  on  the  lever  to  the  pressure 
of  steam  required  in  each  case  by  a  correct  steam  gauge  attached  to  the 
boiler.  The  weight  must  then  be  securely  fastened  in  its  position  and  the 
lever  marked,  for  the  purpose  of  facilitating  the  replacing  of  the  weight 
should  it  be  necessary  to  remove  the  same. 

BULE  37.  All  steam  gauges  heretofore  in  use  oh  steamers  shall  be  ad- 
missible by  the  inspectors,  and  other  steam  gauges  hereafter  made,  of 
equal  merit,  shall  be  allowed. 

RULE  38.  The  appliances  in  use  on  steamers  constructed  prior  to  the 
28th  of  February,  1872,  for  determining  the  height  of  water  in  the  boilers 
shall  be  considered  reliable  low  water  gauges. 

RULE  39.  Every  device  or  appliance  on  board  of  steamers  which  is  by 
law,  or,  in  the  discretion  of  the  inspectors  taken  from  the  control  of  all 
persons  navigating  the  same,  shall  be  secured  as  the  supervising  inspector 
of  the  district  may  direct,  with  the  approval  of  the  Secretary  of  the 
Treasury. 

KULE  40.    There  must  be  means  provided  in  all  boilers  using  "the  low 


136  STEAM  MAKING;  OR,  BOILER  PRACTICE. 

water  gauges"  which  are  operated  by  means  of  a  float  inside  the  same,  to 
prevent  the  float  from  getting  into  the  steam  pipe. 

In  applying  the  hydrostatic  tests  to  boilers  with  a  steam  chimney,  the 
test  gauge  should  be  applied  to  the  "water  line"  of  such  boilers. 

It  shall  be  the  duty  of  local  inspectors  to  report  at  the  end  of  each 
year  to  their  supervising  inspectors,  the  number  of  boilers  inspected  by 
them  in  their  local  districts. 

All  horizontal  cylindrical  boilers  -used  on  steamers  navigating  the 
waters  flowing  into  the  Gulf  of  Mexico,  shall  be  provided  with  a  reli- 
able low  water  gauge. 

EULE  41.  All  boilers,  or  sets  of  boilers,  employed  on  board  of  vessels 
subject  to  the  provisions  of  the  act  of  Congress  relating  to  steam  vessels, 
approved  February  28,  1871,  for  the  purpose  of  generating  steam,  shall 
have  attached  to  them  at  least  one  gauge  that  will  correctly  indicate  the 
pressure  of  steam. 

RELATING  TO  DISCIPLINE. 

KULE  56.  It  shall  be  the  duty  of  an  engineer,  when  he  assumes  charge 
of  the  boilers  and  machinery  of  a  steamer,  to  forthwith  thoroughly  exam- 
ine the  same,  and  if  he  finds  any  part  thereof  in  bad  condition,  caused  by 
neglect  or  inattention  on  the  part  of  his  predecessor,  he  shall  immediately 
report  the  facts  to  the  local  inspectors  of  the  district,  who  shall  there- 
upon investigate  the  matter,  and  if  the  former  engineer  has  been  culpably 
derelict  of  duty  they  shall  suspend  or  revoke  his  license. 


INSTRUMENTS,  MACHINES,  AND  EQUIPMENTS  APPROVED  FOR  USE  ON 
STEAM  VESSELS. 

NOTE.— Only  those  pertaining  to  boilers  are  here  given. 
STEAM  PUMPS. 

Landsell's  double -suction  steam-siphon,  presented  by  H.  S.  Landsell, 
New  York. 

Coil's  single  suction  steam-siphon,  presented  by  Mr.  Coll,  Pittsburgh. 
A.  Sluthouer,  New  Philadelphia,  Ohio,  fire  and  bilge-pump. 
Coil's  improved  steam-siphon  pump. 
Sherriff's  steam-siphon  pump. 

DEVICES  FOR  REMOVING  SEDIMENT  FROM  BOILERS. 

Sediment  agitator,  presented  by  B.  W.  Reynolds,  Evansville,  Indiana. 
John  C.  McLaughlin,  Pittsburgh,  Pennsylvania. 
Armstrongs's  vortex- skimmer. 


THE  DESIGN,  CONSTRUCTION,  ETC.  137 

Ordinary  blow-off  cocks  and  mud- valves. 

LOCK-UP  SAFETY-VALVES. 

H.  G.  Ashton,  East  Cambridge,  Massachusetts. 

Case  &  Baillie,  Detroit,  Michigan. 

J.  I).  Lynde,  Philadelphia,  Pennsylvania. 

Kichardson  &  Co.,  Troy,  NCAV  York. 

Dry-Dock  Engine  Works,  Detroit,  Michigan. 

Cockburn's  safety-valve. 

Ashcroft's  safety-valve. 

Crosby's  safety  valve. 

Morse's  safety-valve. 

Hodgin's  safety-valve. 

A.  Orrne's  safety-valve. 

FEED-WATER  HEATERS. 

Thomas  Koberts,  Baltimore,  Maryland. 

Thomas  Snowden,  Pittsburgh,  Pennsylvania. 

Doyle  &  Keybold,  Delaware  City,  Delaware. 

Charles  G.  Fisher. 

H.  C.  Haskell,  Albany,  New  York. 

Sessler  &  Smith. 

Heerman  &  Smith's  water-back  heater. 

W.  W.  Martin's  feed-water  heater. 

W.  H.  D.  Sweet,  Albany,  New  York. 

STEAM-GENERATORS. 

Mill's  auxiliary  steam-generator.     (Approved  for  use  on  boilers  using 
fresh  water.) 

Herreshoff s  patent  safety  coil-boilers.     (Limited  in  construction  to 
.   pipe  of  4  inches  in  diameter.) 

Farris's  water- circulating  grate  bars,  and  water  fronts. 

GAUGES. 

Shawe's  mercurial  pressure. 
Schaffer  &  Budenberg's  steam-gauge. 

MISCELLANEOUS. 

Torch  for  sailing  vessels,  Nathan  C.  Page. 
Polhamus's  safety-tank  for  fire-room  floors. 
Shelus's  combination  signal  and  flash  light. 
Gerard's  electro -magnetic  fire  and  water -detector. 


1ST8 


STEAM  MAKING;    OR,  BOILER  PRACTICE. 


EXTRACTS  FROM  ENGLISH  BOARD  OF  TRADE  RULES. 

In  Great  Britain,  stationary  boilers  are  built  under  the  inspection  of 
the  Boiler  Insurance  Companies,  and  in  some  towns  are  subjected  to  mu- 
nicipal regulations.  Locomotive  boilers  are  usually  designed  by  the  Sup- 
erintendent of  Machinery,  and  less  commonly  by  the  manufacturer  than  in 
this  country.  Marine  boilers  are  subjected  to  the  control  of  the  Board  of 
Trade,  if  the  vessels  are  designed  to  carry  twelve  or  more  passengers,  but 
freight  steamers  are  not  subject  to  government  inspection,  but  usually  to 
Lloyds  inspection.  We  take  extracts  from  the  rules  of  the  Board  of  Trade 
in  sufficient  number  to  show  how  the  strength  of  the  shell  is  determined. 

When  cylindrical  boilers  are  made  of  the  best  material,  with  all  rivet 
holes  drilled  in  place,  and  all  the  seams  fitted  with  double  butt  straps,  each 
of  at  least  §  the  thickness  of  the  plates  they  cover,  and  all  the  seams  at 
least  double  rivetted  with  rivets  having  an  allowance  of  not  more  than  75 
per  cent,  over  single  shear,  and  provided  that  the  boilers  have  been  open 
to  inspection  during  the  whole  period  of  construction,  then  5  may  be  used 
as  the  factor  of  safety.  The  tensile  strength  of  the  iron  is  to  be  taken  as 
equal  to  47,000  pounds  per  square  inch  with  the  grain,  and  40,000  pounds 
across  the  grain. 

The  boilers  must  be  tested  by  hydraulic  pressure  to  twice  the  work- 
ing pressure,  in  the  presence,  and  to  the  satisfaction  ol  the  Boards'  sur- 
veyors. But  when  the  above  conditions  are  not  complied  with,  the  addi- 
tions in  the  following  scale,  must  be  added  to  the  factor  5,  according  to 
the  circumstances  of  each  case. 


REFERENCE 
LETTERS. 

A 
B 


C 
D 
E* 

F 
G 


AMOUNT 
TO  ADD. 

0.15 
0.3 

0.3 

0.5 

0.75 

0.1 

0.15 


KEASON  FOR  SUCH  INCREASE  IN  FACTOR. 


When  all  the  holes  are  fair  and  in  the  longitudi- 
nal seams,  but  drilled  out  of  place  after  bending. 
When  all  the  holes  are  fair  and  good  in  the  longi- 
tudinal seams  but  drilled  out  of  place  before  bend- 
ing. 

When  all  holes  are  fair  and  good,  but  are  punched 
and  not  drilled  after  bending. 
When  the  holes  are  fair  and  good,  but  are  punched 
and  not  drilled  before  bending. 
When  the  holes  in  the  longitudinal  seams  are  not 
fair  and  good. 

If  the  holes  in  circumferential  seams  are  fair  and 
good,  but  drilled  out  of  place  after  bending. 
If  the  holes  in  the  circumferential  seams  are  fair 
and  good,  but  drilled  out  of  place  before  bending. 


*Allowances  E,  J,  W,  and  X,  may  be  increased  if  the  workmanship  or  material  is 
doubtful  or  unsatisfactory. 


THE  DESIGN,  CONSTRUCTION,  ETC.     • 


139 


EXTRACTS  FROM  ENGLISH  BOARD  OF  TRADE  RULES-CONTINUED. 


REFERENCE 
LETTERS. 


J* 
K 
L 
M 
N 
0 
P 

Q 
R 

S 

T 

U 
V 


w 

X* 


AMOUNT 
TO  ADD. 

0.15 


0.2 


0.2 


0.2 


0.1 


0.3 


0.15 


1.0 


0.1 


0.2 


0.1 


0.1 


0.2 


0.25 


0.4 
0.4 

1.65 


REASON  FOR  SUCH  INCREASE  IN  FACTOR. 


If  the  holes  in  the  circumferential  seams  are  fail 

and  good  but  are  punched  and  not  drilled  after 

bending. 

If  the  holes  in  the  circumferential  seams  are  fair 

and  good,  but  punched  and  not  drilled  before 

bending. 

If  the  holes  in  the  circumferential  seams  are  not 

fair  and  good. 

If  the  longitudinal  seams  are  double  rivetted  lap 

joints,  and  not  double  covered  butts. 

If  the  longitudinal  seams  are  treble  rivetted  lap 

joints  and  not  double  covered  butt  straps. 

If  a  single  butt  strap  double  rivetted  be  used  in 

the  longitudinal  seams. 

If  a  single  butt  strap  treble  rivetted  be  used  in  the 

longitudinal  seams. 

If  the  longitudinal  seams  are  single  rivetted,  either 

lap  single  or  double  butt  straps  being  used. 

If  the  circumferential  seams  are  single  butt  straps 

double  rivetted. 

If  the  circumferential  seams  are  single  rivetted 

single  butt  straps. 

If  the  circumferential  seams  are  double  butt  straps 

single  rivetted. 

If  the  circumferential  seams  are  double  rivetted 

laps. 

If  the  circumferential  seams  are  single  rivetted 

laps. 

When  the  circumferential  seams  are  lap  and  the 

straps  of  plates  are  not  entirely  over  or  under. 

When  the  boiler  is  long  and  flues  are  used,  or  when 

it  is  fired  from  both  ends,  this  does  not  affect  P, 

R,  and  S. 

If  the  seams  are  not  properly  crossed. 

If  there  is  doubt  about  the  metal  being  of  the  best 

quality. 

If  the  whole  process  of  construction  is  not  open 

to  inspection.  


*Allowances  E,  J,  W,  and  X,  may  be  increased  if  the  workmanship  or  material  is 
doubtful  or  unsatisfactory. 


140  STEAM  MAKING;  01?,  BOILER  PRACTICE. 

It  is  usually  stated  on  the  authority  of  Sir  William  Fairbairn  that  a  sin- 
gle-rivetted joint  has  56  per  cent,  of  the  strength  of  the  sheet,  and  that  a 
double-rivetted  lap  has  70  per  cent,  of  the  strength  of  the  sheet.  Under 
these  circumstances  it  can  easily  be  seen  that  6  x  0.56  =  3.36  is  what  is 
taken  as  the  "factor  of  safety"  by  the  Board  of  Supervising  Inspectors, 
and  that  for  steady  pressures  this  is  enough.  Externally  fired  boilers  built 
on  these  rules  are  more  durable  than  if  built  with  a  factor  of  safety  of  6 
or  8,  for  the  metal  does  not  burn  or  the  seams  leak  so  readily.  Seams  leak- 
ing in  the  furnace  cause  rapid  corrosion. 

D.  K.  Clark  concludes  from  some  experiments  by  Brunei  that  for 
wrought-iron  plates  and  rivets,  taking  the  solid  plate  as  100,  the  strength 
of  joints  in  plates  less  than  -/^  of  an  inch  thick,  except  in  the  first  case, 
were  as  follows: 


Double-rivetted  butt  with  two  straps 80 

lap 72 

with  single  welt 65 

Single-rivetted  lap 60 

Concerning  the  strength  of  rivetted  joints,  we  give  some  conclusions 
drawn  by  Professor  A.  B.  W.  Kennedy  on  steel  plates  and  rivets  from  ex- 
periments made  in  1881,  and  taken  from  his  paper  read  before  the  Institu- 
tion of  Mechanical  Engineers,  and  to  be  found  in  Engineering,  vol.  xxxi, 
p.  427  et.  seq. 

For  single-ri vetted  lap  joints  the  best  proportions  are: 


Diameter  of  rivet  =  2.27  x  thickness  of  plate. 
Pitch  *'          =  2.22  diameter. 

For  double-rivetted  lap  joints: 

Diameter  of  rivet  =  2.21  thickness  of  plate. 
Pitch  "          —  3.54  diameter. 


The  rivet  to  be  3^  of  an  inch  smaller  than  the  hole.  The  conclusion 
was  that  with  steel  plates  and  rivets  the  diameter  and  pitch  for  single- 
rivetted  laps  was  such  as  would  exclude  their  use  for  longitudinal  seams, 
and  that  with  more  than  i-inch  plates  the  diameter  of  the  rivet  gets  too 
large  and  the  strength  of  the  joint  is  thereby  reduced.  The.  strength  of  a 
single-rivetted  lap  of  the  proportions  given  above  is  55  per  cent.,  and  the 
double-rivetted  lap  is  77  per  cent,  of  the  plate.  The  strength  of  the  plates 
was  70,000  pounds  tensile,  and  the  rivets  51,000  pounds  shearing  stress. 

We  give  in  more  detail  some  experiments  made  by  Messrs.  Max  Eyth 
and  David  Greig  at  an  earlier  date  than  those  of  Professor  Kennedy,  as  af- 
fording comparative  data  for  iron  and  steel. 


THE  DESIGN,  CONSTRUCTION,  ETC. 


141 


EXPERIMENTS  BY  DAVID  GREIG  AND  MAX  EYTH,  LEEDS,  ENGLAND. 

EXTRACT  FROM  "ENGINEERING,"  PAGE  527,  JUNE  20,  1879. 

TABLE  I.— Tensile  Strain  of  Iron  and  Steel  Rivet  Bars. 


-i 

(3 

s 

o>  ^ 

• 

|| 

1 

22 

S-iM 

|s 

PARTICULARS. 

!i 

| 

<D 

X* 

1 

5? 

*-" 

o  PQ 

6 

i 

EH 

A 

M 

F 

Diameter  in  inches.   ...        

0.625 

0.625 

0.75 

0.75 

0.75 

Area  in  square  inches  

0.307 

0.307 

0.442 

0.442 

0.445 

I.  Breaking  strain,  tons  of  2,240  Its. 

8.85 

6.90 

10.  16 

9.70 

9.70 

II. 

8.84 

6.75 

10.18 

9.90 

9.00 

III. 

8.90 

6.87 

Average  

8.87 

6.84 

10.16 

9.80 

9.25 

Breaking  stress  per  square  inch 

28  83 

22  23 

22  99 

22.17 

20.1)5 

Red  uced  diameter  

0.343 

0.406 

0.500 

0  531 

0.515 

Reduced  area 

0.092 

0  129 

0.196 

0  222 

0  208 

Reduced  to  original  per  cent  
A.  Elongation  per  inch  

30 
0.343 

42 
0.416 

44 
0.'440 

50 
0.343 

47 
0.437 

B.             "              " 

0.206 

0  279 

0  278 

0  225 

0  250 

C.              "               "         

0.171 

0.244 

0.238 

0.195 

0.179 

A.  Is  within  the  2  inches  in  which  the  fracture  occurred. 

B.  Is  within  the  10  inches  in  which  fracture  too  place. 

C.  Is  outside  of  the  2  inches  in  which  fracture  took  place. 

The  tensile  strength  was  30  per  cent,  more  for  the  steel  than  for  the  iron;  the 
ductility  less. 

TABLE  II.— Shearing  Tests  of  Rivet,  Iron  and  Steel. 
(Diameter  of  bars  ^s-inch.    Area  sheared,  0.6136.) 


IN  TONS  OF  2,240  POUNDS. 


Actual  Shearing 
Strain. 

Average. 

Shear  per  Square 
Inch. 

1     Yorkshire  Iron  (Taylors)  

11  825 

2                           " 

11.6 

3               "           "                  .        . 

11  575 

11.665 

19.01 

1.    Steel  (Brown)  

13.45 

2. 

13  65 

3.                                   

13.725 

13.61 

22.18 

TABLE  III.— Burrs  Left.        (Dimensions  in  Inches.) 


IRON. 

STEEL. 

Long  Axis. 

Short  Axis. 

Long  Axis. 

Short  Axis. 

No.  1    . 

0.616 
0.615 
0.621 
0.617 

0.588 
0.587 
0.58:> 
0.586 

0.616 
0.617 
0.616 
0.616 

0.583 
0.588 
0.586 
0.581 

No.  2  

No    3 

Averaee.  .. 

142 


STEAM  MAKING;  OR,  BOILER  PRACTICE. 


TABLE  IV.— Shearing  of  Rivets. 
(Rivets,  5/8-inCh  diameter.    Holes,  11/16-inch  diameter.    Area  sheared,  0.7424  sq.  ln.7 


Material. 

Kind  of  Work. 

IN  TONS  OF  2,240  POUNDS. 

Shear  on  Piece. 

Average. 

Shear  per  square 
inch. 

Yorkshire  Iron.  .  .  . 
Steel  

Hand.  .  . 
Hydraulic 

14.95 
15.425 
16.01 
18.925 
19.320 
20.4 

15.46 
19.485 

20.8 
26.3 

Steam  .  .  . 
Hand  

Hydraulic 

"     

Steam  

TABLE  V.— Shearing  of  Steel  Rivets. 
(Rivets,  5/8-inch  diameter.    Holes,  11/16-inch  diameter.    Area  sheared,  0.7424  sq.  in.) 


KIND  OF  WOKK. 

Letter. 

Actual  Shear. 

Average. 

Tons  of  2240  Its. 
per    square    inch  . 

Steam  Riveter 

a 

19  5 

b 

18  '.75 

c 

18.95 

19.07 

25.75 

Stationary  Hydraulic. 

a 

17.8 

b 

17.05 

c 

18.05 

17.63 

23.80 

Portable  Hydraulic... 

a 

16.70 

b 

16.85 

c 

17.11 

16.88 

22.78 

Power  Light  Blow. 

a 

16.67 

b 

16.68 

16.67 

22.50 

Power  Heavy  Blow  — 

c 

17.6 

17.6 

23.76 

The  pressures  on  the  heads  of  |  rivets  were: 

Lbs. 

Steam  Rivetter 82,380 

Hydraulic  Stationary 86,360 

Hydraulic  Portable 44,018 

Power  Light  Blow 69,384 

Power  Heavy  Blow 115,640 

TABLE  VI.— Shearing  of  Steel  Rivets. 
(Rivets,  5/8-inch  diameter.    Holes,  11/16-inch  diameter.    Area  sheared,  0.7424  sq.  in.) 


Number. 

Pressure  on  Rivet  Head. 

Actual  Shearing. 

Pounds. 

Tons  of  2240  Its. 

1 

18.4 

2 

39,922 

18.75 

3 

83,133 

19.1 

4 

84,542 

19.337 

5 

88,299 

19.775 

6 

19  95 

7 

19.05 

Average. 

19.05 

THE  DESIGN,  CONSTR  UC TION,  ETC.    ' 


143 


TABLE  VII.— Rivet  Tests. 
(Rivets,  5/8-inch  diameter.    Holes,  11/16-inch  diameter.    Area  sheared,  0.7424  sq.  in.) 


I. 

II. 

III. 

IV. 

V. 

Steam. 

Hydraulic  . 

Hydraulic. 

Power. 

Power. 

Pressure  on  head  

83280 

86360 

42018 

69384 

115640 

Breaking  strain  of  sample  — 
Shearing  strain  of  sample  — 
Friction  of  sample    

42717 
36885 
5832 

39491 
36885 
2606 

37811 
36885 
926 

37341 
3688.'5 
456 

39424 
36885 
2539 

Friction  of  strain  on  one  sur- 
face   

2916 

1303 

463 

228 

1269 

CONCLUSIONS    DRAWN   FROM  VERY  EXTENDED  EXPERIMENTS,   BY 
DAVID  GREIG  AND  MAX  EYTH,  OF  LEEDS. 

ABSTRACTED  FKOM  "ENGINEERING,"  p.  581,  JUNE  27,  1879. 

"It  would  be  premature  to  take  any  of  the  conclusions  which  can  be 
"drawn  from  the  above  tests  as  final,  as  in  all  practical  questions,  experi- 
"ence  will  have  to  supplement  experiment,  before  any  absolutely  definite 
"results  are  arrived  at.  But  a  few  facts  may  be  pointed  out,  which  seem 
"to  be  clearly  indicated  by  the  results  of  the  tests,  and  which  at  least  show 
"the  direction  in  which  further  investigation  may  be  usefully  conducted, 
"and  where  practical  improvements  are  specially  required. 

"There  is  no  doubt,  whatever,  that  the  manufacturers  of  steel  are  now 
"able  to  produce  a  material  as  homogeneous  and  reliable  as  the  best  iron. 
"The  absence  of  lamination  makes  it  in  this  respect,  even  superior  to  iron 
"for  a  structure  like  a  boiler,  in  which  the  plates  are,  as  a  rule,  exposed  to 
"strains  in  every  direction. 

"But  this  result  has  been  obtained  by  reducing  the  hardness  of  steel 
"to  a  minimum,  which  materially  reduces  its  increased  usefulness.  The 
"tensile  shearing  strength  of  the  material  supplied  for  these  tests  by  some 
"of  the  most  experienced  makers  of  steel,  and  by  them  no  doubt,  consid- 
"ered  the  best  for  the  purpose,  has  in  these  experiments  proved  to  be  not 
"more  than  16  per  cent,  above  that  of  the  iron,  and  the  want  of  hardness 
"(as  distinct  from  tensile  strength)  has  proved  to  be  a  very  serious  disad- 
"vantage  in  boiler  work.  What  the  trade  now  requires  is  "a  return  to  a 
"harder  material  of  increased  tensile  strength,  without  losing  the  homo- 
"geniety,  which  at  present  is  obtained  at  the  expense  of  hardness.  It  can 
"scarcely  be  doubted  that  the  increasing  experience  in  the  manufacture  of 
"steel,  which  has  already  overcome  so  many  and  such  serious  difficulties, 
"will  in  time  meet  this  requirement. 


144  STEAM  MAKING;  OR,  BOILER  PRACTICE. 

"The  well-known  fact  of  the  superiority  of  rivetting  by  machinery 
"over  hand-rivetting,  has  been  again  demonstrated  most  conclusively, 
"while  the  experiments  have  shown  that  the  effects  of  steam  rivetting  is 
"to  say  the  least  of  it,  not  inferior  to  hydraulic  rivetting  as  far  as  the  quality  of 
"the  rivet  is  concerned  but  that  the  hydraulic  rivetting  is  distinctly  superior 
"as  to  its  effects  on  the  plate,  which  is  less  injured  by  the  slow  pressure  of 
"the  hydraulic  ram. 

"A  number  of  curious  facts  referring  to  rivetted  joints  were  indicated 
"by  the  trials.  Steel  showed  in  this  respect  a  decided  superiority  over 
"iron  beyond  the  proportion  due  to  its  greater  tensile  and  shearing  strength, 
"the  average  strength  of  all  the  steel  seams  broken  being  60  per  cent,  of 
"the  solid  plates,  that  of  iron  only  54  per  cent.  This  proportion  was  still 
"more  striking  in  all  lap  joints,  in  which  the  greater  stiffness  of  the  ma- 
"terial  prevented  the  injurious  bending  of  the  plates  in  the  line  of  the 
"rivets,  this  being  no  doubt  the  chief  cause  of  the  great  weakness  of  this 
"kind  of  joint. 

"The  experiments  further  show  that  the  plates  invariably  lose  part  of 
"their  tensile  strength  in  the  section  of  solid  material  left  between  the 
"rivets  of  a  seam,  this  loss  being  greatest  in  lap  joints.  It  is  also  greater 
"in  punched  than  in  drilled  plates,  (iron  as  well  as  steel)  and  greater  in 
"plates  rivetted  together  by  steam,  than  in  those  rivetted  by  hydraiilic 
"pressure.  On  the  other  hand,  the  strength  of  rivets  against  shearing 
"is  greater  than  its  normal  figure,  especially  in  lap  joints. 

"The  usefulness  of  double  rivetting  appears  to  be  mainly  due  to  the 
"fact  that  it  more  effectually  prevents  lap  jointed  plates  from  bending 
"under  stress.  At  the  same  time  the  zig-zag  rivetting  generally  adopted, 
"in  double  rivetting,  increases  the  tensile  resistance  of  the  material  be- 
"tween  the  rivets  considerably  beyond  its  normal  figure. 

"Butt  joints  with  a  cover  on  one  side  of  the  plate,  only  gave  no  advan- 
tage at  all,  the  cover  behaving  simply  as  an  intermediate  plate  attached 
"to  the  two  main  pieces  by  an  ordinary  lap  joint.  A  marked  improvement 
"could,  no  doubt,  be  obtained  by  giving  the  cover  greater  thickness,  so  as 
"prevent  its  bending. 

"The  most  effective  seams  as  to  tensile  strength,  were  of  course,  butt- 
joints  with  two  covers,  as  not  only  do  they  nearly  double  the  shearing 
"strength  of  each  rivet,  but  they  entirely  prevent  the  bending  of  the  main 
"plates.  The  main  fact  resulting  from  the  tests  of  parts  of  boilers  and 
"complete  boilers  under  hydraulic  pressure  was  the  impossibility  of  burst- 
ing an  ordinary  rivet  seam  in  this  way,  the  compression  of  the  rivet  and 
"the  elongation  of  the  rivet  hole,  resulting  invariably  in  leakage,  which 
"prevented  the  necessary  pressure  from  being  obtained.  Each  rivet  be- 
"  comes  its  own  safety  valve,  and  the  strain  put  on  the  weakest  part  of  the 
"structure,  never  reached  more  than  70  per  cent,  of  the  breaking  strain. 
"This  is  the  point  where  additional  hardness  of  the  material  would  be 
"most  useful,  as  it  would  prevent  the  opening  of  the  rivet  holes,  which 
"now  makes  a  boiler  useless  long  before  the  breaking  strain  is  reached. 

"On  the  question  of  the  durability  of  boilers  it  is  probably  impossible 


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146 


STEAM  MAKING;  OR,  BOILER  PRACTICE. 


"to  throw  much  light  by  experiments.  Here  practical  experience  is  the 
"only  reliable  guide,  and  every  well  authenticated  example  is  of  some 
"value.  The  paper  may  therefore  be  concluded  with  the  mention  of  one 
"such  example  which  presented  itself  for  careful  examination  during  the 
"last  few  weeks.  Two  boilers  similar  in  construction  to  those  experimen- 
ted upon  were  constructed  by  Messrs.  John  Fowler  &  Company,  in  the 
"Spring  of  1868,  one  being  entirely  of  steel  and  the  other  of  iron.  They 
"were  used  for  the  two  engines  of  a  steam  ploughing  tackle,  and  have  just 
"returned  for  repairs  to  the  manufacturers  after  eleven  years  of  work,  dur- 
"ing  which  they  had  been  provided  with  new  fire-boxes  in  1874. 

"During  the  whole  time  these  boilers  had  to  go  through  the  severest 
"work  and  treatment  to  which  boilers  can  be  exposed,  using  every  variety 
"of  the  worst  water,  travelling  over  the  roughest  roads  and  being  exposed 
"to  every  sort  of  weather  without  external  protection.  Both  boilers  also 
"had  to  do  exactly  the  same  amount  of  work  and  to  undergo  the  same 
"hardships  as  neither  of  the  two  engines  can  work  without  the  other.  The 
"result  is  most  striking.  The  steel  boiler  has  never  given  any  trouble  and 
"is  now  by  far  the  best  of  the  two.  A  few  cases  of  this  description  should 
"finally  settle  the  question  as  to  the  superiority  of  steel  in  this  respect. 

Note  the  conclusion  regarding  leakage  under  pressure:  it  is  exactly 
what  the  Lancashire  boiler  experiment  disproved,  when  the  material  was 
wrought-iron.  We  suppose  the  quantity  of  water  which  can  be  furnished 
in  a  given  time  is  the  most  important  element  in  this  question. 

With  regard  to  all  flat  surfaces  under  pressure,  the  usual  practice  is  to 
stay  or  tie  the  flat  surface  either  to  the  shell  or  to  some  other  more  or  less 
adjacent  parallel  or  nearly  parallel  flat  surface.  Sometimes  the  flat  sur- 
face is  stiffened  by  rivetting  an  angle  or  T-iron  on  it,  and  often  the  ties  used 
are  attached  by  means  of  tee  or  angle  irons  to  the  flat  surface,  or  to  the 
shell.  When  the  flat  surface  is  exposed  to  the  fire  it  is  usual  to  screw  the 
tie  bolts  directly  into  the  sheet. 

The  conclusions  arrived  at  by  a  Board  of  Engineers  who  made  nu- 
merous experiments  at  the  Washington  Navy  Yard  are  as  follows,  taken 
from  report  of  the  Bureau  of  Steam  Engineering,  United  States  Navy,  for 
1879: 

FOR  PLATES  AND  TIE  BOLTS  SCREWED  THEREIN: 


Thickness  of  sheet. 

Diameter  of  bolt. 

Threads  per  inch. 

Bolt  projected. 

r 

1" 

14 

k" 

i" 

ir 

14 

y 

i" 

U" 

12 

¥ 

r 

n" 

12 

v 

THE  DESIGN,  CONSTRUCTION,  ETC. 


147 


FOR  PLATES  AND  TIE  BOLTS  SCREWED  THEREIN : 


IF  BIVETTED  TO   CONE  HEADS. 

IF  NUTS  ARE  USED. 

Projection  of  head. 

Diameter  of  base 
of  cone. 

Breadth  of  annu- 
lar bearing  sur- 
face. 

Dished  out   to   a 
depth  of 

iV 

w 

jY' 

h" 

r 

iiV 

i" 

tf 

xV 

If" 

iV 

A" 

I" 

11" 

V 

A" 

For  the  bursting  pressure  in  pounds  per  square  inch  multiply  the 
square  of  the  quotient,  arising  by  dividing  the  thickness  of  plate  by  the 
distance  apart,  center  to  center  of  bolt,  by  the  constant  which  follows: 

For  iron  plates  and  iron  bolts 192,000 

For  steel  plates  andiron  bolts 200,000 

For  steel  plates  and  low  steel  bolts 224,000 

For  iron  plates  and  iron  bolts  with  nuts 320,000 

For  copper  plates  andiron  bolts 116,000 


The  large  diameter  of  bolt  used  is  probably  intended  to  resist  corro- 
sion. In  locomotive  practice  |-inch  bolts  are  used  for  j^-inch  sheet  with 
not  more  than  5-inch  centres.  It  must  not  be  forgotten  that  much  of  the 
straining  and  leaking  at  stay  bolts  is  caused  by  the  movements  of  the 
sheet  by  expansion,  and  that  the  longer  the  bolt  the  less  action  of  this 
kind  takes  place  on  the  sheet. 

The  proportion  of  eye-bars  for  tie  stays  was  determined  by  the  same 
Board,  but  the  results  are  not  in  harmony  with  the  practice  of  bridge 
builders  in  the  use  of  eye-bars,  and  we  shall  therefore  take  the  latter  as 
safer  practice. 

The  proportions  found  safe  by  experiment  on  full  size  eye-bars,  are 
that  the  sum  of  the  sectional  areas  of  metal  on  each  side  of  the  eye  should 
be  50  per  cent,  in  excess  of  that  in  the  body  of  the  bar,  and  that  there 
should  be  behind  the  eye  in  a  plane  through  the  centre  of  the  bar,  metal 
enough  in  the  section  to  equal  that  in  the  body. 

On  the  strength  of  fl-ues  against  external  pressure  little  is  really  known. 
Sir  William  Fairbairn  made  some  experiments  on  this  matter,  and  to  him 
is  due  the  rules  commonly  used,  given  hereafter.  Mr.  D.  K.  Clark  gives 
other  values,  and  a  controversy  took  place  a  few  years  ago  on  the  subject 
in  the  columns  of  Engineering,  and  we  add  a  few  experiments  made  by  the 
manufacturers  of  the  Fox  Corrugated  Flue.  The  boilers  tested  by  the 
Lancashire  Steam  Users'  Association,  and  by  John  Elder  &  Co.,  which  we 
give  in  the  next  chapter,  show  flues  stronger  than  shell,  which  is  to  be  de- 


148  STEAM  MAKING;  OR,  BOILER  PRACTICE. 

sired.  The  corrugations  certainly  have  greatly  increased  the  strength  of 
such  flues,  but  at  present  such  corrugated  flues  are  made  only  by  one  firm 
in  England  and  by  one  in  Germany.  It  has  been  proposed  to  make  tubes  of 
cone  frustra  with  flange  and  ring  joints,  making  a  difference  of  say  4  to  6 
inches  for  each  foot  in  length.  By  this  device  sheets  of  ^-inch  thickness 
could  be  used  up  to  4  feet  diameter  for  high  pressures.  There  are,  how- 
ever, no  data  upon  this  matter.  We  add  the  experiments  on  full- sized 
flues  and  boilers  in  the  next  chapter. 

Fairbairn's  rule  is  that  the  collapsing  pressure  in  pounds  per  square  inch 
is  equal  to  806,000  times  the  2.19  power  of  the  thickness  in  inches  divided  by 
the  product  of  the  diameter  in  inches  times  the  unstayed  length  in  feet. 

Fairbairn's  rule  ao  usually  given,  is  the  collapsing  pressure  in  pounds 
per  square  inch  is  equal  to  806,000  times  the  square  of  the  thickness  in  in- 
ches divided  by  the  product  of  the  diameter  in  inches  times  the  unstayed 
length  in  feet. 

D.  K.  CLAEK'S  RULES. — For  tubes  up  to  6  inches,  collapsing  pressure  = 

thickness  x  (  112'000 I2,00o).   Over   6  inches,  collapsing  pressure  = 

V  diameter  / 

thickness  (     5t)>OQO 5,OOoV     Some  experiments  made  in  Washington 

\  diameter  / 

in  1874,  agreed  with  the  Fairbairn  rule  and  did  not  give  much  increase  of 
strength  from  an  Adamson  joint. 

Clark  states  the  average  compression  on  the  metal  of  the  tube  for  col- 
lapsing is  about  2  tons  per  square  inch,  and  that  the  influence  of  length  is 
uncertain. 


CHAPTER     VII. 


DESIGN  AND  CONSTRUCTION  CONTINUED— PROPORTIONS  OF  HEATING  SUR- 
FACE, ETC.— ECONOMIC  EVAPORATION— EXPLOSIONS. 

EXPERIMENTS  ON  THE  COLLAPSING  OF  FLUES. 

Experiments  at  Washington  Navy  Yard  in  1874. — An  external  shell  with 
one  end  flanged  inward  and  then  longitudinally,  and  with  a  similar  flange 
fitted  inside  the  other  end,  was  made  63  inches  diameter,  g-inch  thick,  and 
a  flue  77£  inches  long  and  54  inches  inside  diameter  was  rivetted  to  the 
flanges. 

The  flue  was  in  two  rings  of  J"  iron  with  an  inside  strap  7f  "x  £".  Each 
ring  was  in  two  plates  with  inside  strap  7f"x  £",  and  all  seams  were  double 
rivetted  and  caulked.  Slightly  oval.  It  was  collapsed  and  then  shored  across 
at  105,  120,  148,  155,  180  pounds.  Another  flue  of  £  iron  made  as  before, 
except  with  an  Adamson  joint  with  ^  ring  bar,  and  a  true  cylinder:  one 
ring  collapsed  at  133  pounds,  and  then  the  other  at  130. 

Experiments  were  made  comparing  the  collapsing  pressure  of  plain 
and  corrugated  flues. 

FLUE  TESTS  FBOM  "ENGINEERING,"  p.  245,  MARCH  29,  1878. 

TABLE  A.— Plain  Flue. 
(3'  1M"  outside  diameter.    7'  long,  %"  thick.) 

_   I  Horizontal  diameter  before  pressure 36. 65  inches . 

a  I  Vertical  diameter  before  pressure 37. 20 

7    j  Horizontal  diameter  before  pressure 36  62 

u   I  Vertical  diameter  before  pressure 36.77 


POUNDS  PER 
SQUARE    INCH. 

POSITION  IN 
TUBE. 

DEFLECTION. 

SET. 

Horizontal. 

Vertical. 

Horizontal. 

Vertical. 

25 

a 

+ 

0 

0 

+ 
0 

0 

50 

a 

0.02 

0 

0 

0 

75 

a 

0.02 

0.02 

0 

0.02 

100 

a 

0.02 

0.04 

0 

0.02 

25 

a 

0.02 

0.04 

0 

0.02 

150 

ja 

la 

0.03 
0.00 

0.04 
0.03 

0 
0 

0.02 
0 

175 

ja 

i& 

0.03 
0 

0.04 
0.05 

0 
0 

0.04 
0 

200 

a 

gave  way 

gave  way 

gave  way 

gave  way 

By  the  Fairbairn  formula  this  should  have  stood  350  pounds. 


150 


STEAM  MAKING;    OB,  BOILER  PRACTICE. 


TABLE  B.— Corrugated  Flue. 
(Corrugations  6"  pitch,  1 5/16"  deep,  metal  3/8"  thick.) 

j  Horizontal  diameter  before  pressure 35 .18  inches. 

)  Vertical  diameter  before  pressure 35 . 60 

i    I  Horizontal  diameter  before  pressure 35.31 

1  Vertical  diameter  before  pressure 35.25 


POUNDS  PEE 
SQUARE    INCH. 

POSITION  IN 
TUBE. 

DEFLECTION. 

SET. 

Horizontal. 

Vertical. 

Horizontal. 

Vertical. 

200 

a 

+ 
0 

0 

+ 
0 

0 

b 

0 

0 

0 

0 

250 

a 

0 

0.01 

0 

0 

b 

0.01 

0.01 

0 

0 

300 

a 

0 

0.02 

0 

0 

6 

0.01 

0.03 

0 

0 

350 

a 

0 

0.05 

0 

0 

b 

0.01 

0.05 

0 

0 

400 

a 

0.05 

0.10 

0.04 

0.02 

b 

0.02 

0.10 

0.04 

0 

450 

a 

gave   way, 

the    weld 

proved 

imperfect 

Another  tube  of  same  dimensions  failed  with  1,070  pounds. 

TESTS  MADE  BY  THE  MANCHESTER  STEAM  USERS'  ASSOCIATION  UPON  A 
LANCASHIRE  BOILER. 


EXTEACT  FEOM  "ENGINEEBING,"  P.  234,  MABCH  24,  1876. 

"The  proposition  to  construct  an  experimental  boiler  to  be  tested  by 
"hydraulic  pressure  up  to  the  bursting  point,  was  submitted  to  the  Asso- 
"ciation  by  their  Executive  Committee  through  their  chief  engineer's  re- 
port, as  far  back  as  the  month  of  June,  1874.  Its  desirability  appeared 
"evident  to  the  committee,  especially  with  regard  to  the  weakening  effect 
"of  openings  cut  for  man-holes,  steam  necks,  etc.,  which  it  was  firmly  be- 
lieved tended  more  to  the  rupture  of  boiler  shells,  than  was  usually  ad- 
"mitted. 

"It  was  therefore  arranged  that  a  proper  boiler  should  be  constructed 
"of  the  diameter  adopted  in  daily  practice,  and  of  the  usual  thickness 
"of  plates  with  actual  man-hole  mouth-piece,  etc.,  such  as  are  common,  so 
"that  the  ultimate  test  should  be  decisive. 

"With  this  object  then  in  view,  they  had  a  boiler  constructed  21  feet 
"long,  by  7  feet  diameter  inside  the  inner  plate  of  shell*  with  two  furnace 


DEK1GN  AND  (JONSTRUGTION  CONTINUED,  ETC. 


151 


"tubes  2  feet  9  inches  inside  diameter,  with  flanged  seams,  each  ring  be- 
"ing  welded  up  solid  so  that  there  would  be  no  rivets  or  lap-joints  in  the 
"flue.  The  shell  plates  were  iVimch  thick,  the  ends  welded  up  solid  were 
"i-inch  thick,  and  the  furnace  tubes  of  f -inch  plate,  the  material  through- 
put being  of  best  best  Snedshill  iron.  All  longitudinal  joints  were  double 
"rivetted  and  circumferential  ones  single  rivetted.  Kivet-holes  were 
"punched.  The  rivets  were  2f  inches  centre  to  centre  and  the  holes  a  mean 
"diameter  of  ||-inches." 

In  the  first  experiment  the  boiler  was  complete;  the  man-hole"  mouth- 
piece on  second-plate  from  back  was  of  wrought-iron  as  recommended  by 
the  Association,  the  cast-iron  pipe  for  blow-off  elbow  to  attach  to  was  also 
as  usual,  while  the  gusset  stays  and  longitudinal  stays  were  such  as  pro- 
vided for  75  pounds  working  pressure.  The  front  man-hole  was  placed  on 
the  inside  of  the  front  plate  and  furnished  with  usual  door  and  cross-bar 
fittings.  The  wrought-iron  neck  on  the  top  of  the  central  sheet  was  the 
special  object  of  the  first  experiment.  The  hole  in  the  sheet  was  17  inches 
in  diameter,  and  the  neck  16  inches  inside  by  llf  inches  high,  covered 
with  a  wrought-iron  plate;  the  neck  was  flanged  and  held  on  by  32  rivets. 
Careful  records  were  taken  of  the  behavior  of  all  parts  of  the  boiler  as  the  pres- 
sure rose.  The  flat  ends  were  carefully  gauged  to  ascertain  at  what  pres- 
sure and  to  what  extent  they  gave  away,  and  if  any  permanent  set  re- 
mained after  the  pressure  was  relieved.  The  furnace  flues  were  carefully 
gauged.  The  length  of  the  shell  was  measured  by  rods  fixed  at  one  end 
and  free  at  the  other,  having  pointers  at  several  places.  The  circumfer- 
ence was  measured  by  two  encircling  steel  bands  passed  around  the  boiler 
and  weighted  at  each  end,  so  that  by  horizontal  lines  drawn  across  them, 
the  least  englargement  could  be  rendered  clearly  visible. 

The  first  rupture  took  place  at  the  base  of  the  wrought  iron  neck,  with 
250  pounds  pressure;  up  to  this  point  there  was  no  movement  of  the  ends 
beyond  a  slight  permanent  set  which  did  not  increase,  by  which  fact  the 
sufficiency  of  the  gusset  stays  to  secure  the  ends  was  clearly  shown. 

The  boiler  having  been  repaired  by  rivetting  a  thick  plate  over  the 
hole  whence  the  neck  had  been  removed,  was  furnished  with  a  cast-iron 
man -hole  mouth-piece  of  the  usual  form.  This  casting  was  1  inch  thick, 
8  inches  high,  and  16|  inches  inside  diameter  upon  a  20-inch  opening. 
The  casting,  which  was  sound,  gave  way  with  200  tbs.  per  square  inch  pres- 
sure. For  the  third  experiment,  a  dome  3  feet  in  diameter  was  used,  only  a 
small  portion  of  the  shell  having  been  cut  away,  but  with  235  pounds  the 
base  leaked  so  that  no  increase  could  be  obtained.  The  base  being  stiff- 
ened by  the  use  of  rivets  with  heavier  heads  rupture  of  the  dome  flange 
took  place  with  260  pounds.  No  signs  of  trouble  had  been  noted  in  the 
flues  and  ends,  nor  any  strain. 

The  fifth  test  was  made  with  a  single  rivetted  joint  in  a  longitudinal 
seam,  which  leaked  with  250  pounds,  and  no  increase  of  pressure  could  be 
obtained,  while  the  double  rivetted  seams  had  all  remained  tight. 

The  sixth  test  was  made  with  the  ordinary  oval  man-hole  in  the  shell; 
it  was  17  inches  by  13  inches,  and  no  strengthening  ring  was  used.  Every- 


152  STEAM  MAKING;  OR,  BOILER  PRACTICE. 

thing  was  new  of  course,  and  in  proper  order,  but  the  head  blew  out  of  the 
shell  with  200  pounds. 

Test  seven  was  to  see  if  a  rent  could  be  made  with  the  leaky  seam  of 
the  single  ri vetted  joint,  with  augmented  pumping  power;  the  sheet  gaye 
way  along  the  seam  and  extended  into  both  adjacent  ring  sheets  with  275 
pounds.  The  single  rivetted  seam  was  machine  work.  A  doubls  rivetted 
hand-made  seam  was  then  compared  with  the  machine  work,  giving  way 
with  300  pounds,  while  the  machine  work  remained  intact. 

When  the  boiler  was  again  made  good,  a  somewhat  unexpected  frac- 
ture took  place  at  the  cast-iron  flange  connection  for  the  blow-off,  which 
gave  way  at  300  pounds,  tearing  the  shell:  after  repairing  this,  the  final 
test  was  made,  when  the  centre  seam  at  the  bottom  and  middle  of  the 
boiler  gave  way  with  310  pounds  per  square  inch.  The  calculated  strength 
of  the  double  rivetted  seams  was  320  pounds.  The  whole  of  the  work 
was  done  by  Mr.  Thomas  Beeley,  of  Hyde  Junction  Iron  Works,  near 
Manchester, 
i 

FBOM  "ENGINEERING,"  PAGE  47,  JULY  21,  1876. 

Experiments  made  by  Messrs.  John  Elder  &  Company,  to  test  the  ulti- 
mate strength  of  a  boiler  and  super-heater  removed  from  the  S.  S.  "Ban- 
righ, "  of  the  Aberdeen  &  London  Steam  Navigation  Company. 

The  boiler  was  one  of  a  pair,  which  with  the  super-heater,  had  been 
six  years  in  service,  and  which  were  to  be  replaced  by  new  ones. 

GENERAL  DESCRIPTION. 

The  ship  contained  two  boilers  fired  from  both  ends,  the  products  of 
combustion  being  led  over  them  in  a  flue  of  sheet-iron  passing  up 
through  the  flue  of  a  super-heater  or  steam  drum  forming  the  lower  part 
of  the  funnel.  The  boilers  were  made  in  the  year  1870,  and  were  removed 
after  being  worked  hard  and  continuously  for  six  years.  About  three  years 
ago  both  boilers  and  super-heater  underwent  extensive  repairs.  The 
plates  under  and  at  the  side  of  the  bridges,  the  lower  screwed  stays,  the 
first  row  of  longitudinal  stays  over  the  tubes,  and  the  tubes  being  re- 
moved. The  shell  at  bottom  and  on  each  side  of  the  water-line,  showing 
pitting,  was  lined  with  iron  plates  bolted  on  inside.  The  flue  of  the  super- 
heater was  then  entirely  renewed.  The  dimensions  of  the  boilers  were  as 
follows: 

BOILER. 

Mean  diameter  of  shell 11'    4%" 

Length  of  shell • 12'    6" 

Diameter  of  furnaces  (Gin  number) 2'  10" 

Diameter  of  tubes  outside  (404) 2^" 

Thickness  of  shell  plates H" 

Thickness  of  tube  plates Hit 

Thickness  of  furnace  tops  and  fire-boxes 7/16" 

Thickness  of  furnace  bottoms J6 


DESIGN  AND  CONSTRUCTION  CONTINUED,  ETC.  153 

Thickness  of  tubes No.  9,  B.  W.  G 

Thickness  of  stay  tubes ; %"' 

Stays  distance  center  to  center  in  steam  space 14"  X  ii"  to  12" 

Stays  distance  center  to  center,  fire-box  sides 6"  X  7" 

Diameter  of  18  long  stays  in  steam  space,  in  3  rows,  4,  C,  and  8 1%" 

Diameter  of  other  stays • 1^4" 

SUPERHEATER. 

Mean  diameter  shell 8'  4% " 

Mean  diameter  flue 5'  6V 

Length 8'  0  ' 

Thickness  shell  plates 9/16" 

Thickness  flue  plates 9/16" 

The  boilers  originally  carried  a  certificate  from  the  Board  of  Trade  for 
a  pressure  of  60  pounds,  which  after  the  repairs  above  mentioned,  was  re- 
newed, and  a  year  ago  in  1875  the  pressure  was  reduced  to  55  pounds. 

General  Arrangement  of  Experiment. — The  experiment  was  conducted 
in  the  following  manner.  One  boiler  and  the  super-heater  were  connec- 
ted each  to  the  pumps  by  a  pipe  1  inch  in  diameter,  which  worked  the  hy- 
draulic cranes,  whereby  a  good  supply  of  water  was  at  command  up  to  800 
pounds  per  square  inch;  on  each  a  pressure  gauge  which  had  been  care- 
fully tested  previously  was  fixed,  and  the  experiment  was  conducted  by 
raising  the  pressure  in  both  boiler  and  super-heater  successively  to  120 
pounds,  180  pounds,  and  210  pounds,  at  each  of  which  pressures  the  boiler 
and  superheater  were  carefully  gauged,  the  boiler  bursting  at  230  pounds 
and  the  superheater  at  245  pounds  per  square  inch.  At  120  pounds  there 
was  no  leakage;  at  180  pounds,  a  little  water  trickled  at  some  of  the  longi- 
tudinal joints  of  the  shell  and  at  some  three-ply  rivets  at  the  junction  of 
the  tube  plates  and  furnace  crown,  which  had  been  rather  severely  acted 
on  by  the  fire,  and  had  evidently  been  repaired  at  some  former  time.  At 
210  pounds  the  leakage  in  the  shell  increased,  while  that  in  the  furnace 
crowns  seemed  nearly  constant.  Up  to  the  time  of  bursting,  the  leakage 
in  the  shell  was  not  serious,  and  the  only  leakage  in  the  furnaces  was  at 
the  rivets  above  described.  All  the  rest  of  the  boiler,  the  furnaces,  tubes, 
fire-boxes,  tube-plates,  and  ends,  were  perfectly  tight  and  no  signs  either 
before  or  after  the  boiler  burst  could  be  detected  in  the  appearance  of  the 
caulking  or  otherwise  that  these  parts  had  been  subjected  to  pressure. 

Superheater.— At  120  pounds  there  was  no  leakage,  at  180  pounds  a 
little  water  trickled  at  the  longitudinal  joints  in  the  shell,  and  a  few  drops 
leaked  slowly  in  the  flue.  At  210  pounds  the  longitudinal  joints  of  the 
shell  leaked  very  considerably,  while  the  leakage  in  the  flue  increased  but 
slightly.  At  230  pounds  the  leakage  at  these  joints  in  the  shell  became  so 
great  that  the  pumps  could  not  raise  the  pressure  higher,  and  one  of  these 
joints  had  to  be  severely  caulked  three  times  before  the  pressure  could  be 
raised  to  245  pounds,  at  which  pressure  one  of  the  joints  opposite  to  the 
one  which  had  been  caulked  gave  way. 

The  fracture  of  the  boiler  commenced  at  230  pounds,  without  warning, 
almost  simultaneously  in  two  places:  one  along  a  longitudinal  seam,  the 
other  where  the  thickness  had  been  much  reduced  by  fitting;  it  instantly 


154  STEAM  MAKING;  OX,  BOILER  PRACTICE. 


extended  through  a  sheet,  and  the  next  seam  on  one  end,  and  through  the 
front  angle  iron  and  tube  plate  on  the  other.  The  impression  was  that  it 
began  on  the  double  rivetted  seam.  The  rivetting  was  chain,  not  zigzag. 
The  tensile  strength  of  the  plates  determined  by  Mr.  Kirkaldy,  was  from 
42,000  to  48,000  pounds.  The  failure  in  the  superheater  was  with  37,000 
pounds  nearly,  and  in  the  boiler  with  36,500  pounds,  tension. 

Next  in  importance  to  the  strength  of  a  boiler  is  its  durability,  and  it 
has  been  said  that  durability  is  a  function  of  accessibility;  be  this  as  it 
may,  it  is  certainly  extremely  important  to  provide  an  access  to  all  parts 
of  a  boiler  both  inside  and  out  for  the  purpose  of  inspection  and  cleaning, 
which  sometimes  requires  the  use  of  a  scraper  or  even  a  chisel  to  detach 
scale.  The  destruction  of  a  boiler  may  be  caused  by  corrosion  from  the 
outside  or  from  the  inside,  by  overheating  caused  by  scale  or  by  low  water, 
or  by  the  movements  and  strain  caused  by  changes  of  temperature. 

Internal  corrosion  is  usually  caused  by  chemical  action  of  substances 
held  in  solution  by  the  water.  The  action  of  oxygen  in  causing  pitting  or 
small  spots  of  rust,  is  common  in  boilers  which  use  water  from  surface 
condensers,  especially  when  the  boiler  is  laid  off  frequently  and  emptied 
often.  Water  condensed  in  heating  buildings  absorbs  much  of  the  air 
which  comes  into  the  pipes  whenever  the  pressure  falls  below  the  atmos- 
phere, and  such  boilers  are  best  kept  full  of  water  when  not  in  use. 

In  boilers  supplying  steam  to  engines,  there  is  often  trouble  from  the 
oil  brought  over  from  the  cylinder,  either  from  the  condenser  or  from  an 
open  heater,  and  then  decomposed  by  the  heat  into  some  one  or  more  of 
the  "fatty  acids."  The  use  of  only  mineral  oils  in  the  cylinder  will  pre- 
vent most  of  this  action,  while  in  some  cases  lubrication  of  the  cylinders 
has  been  abandoned  altogether,  generally  for  the  purpose  of  preventing 
foaming  in  boilers  which  are  crowded  to  the  extent  of  their  capacity. 

External  corrosion  occurs  usually  at  places  where  leakage  of  water,  or 
steam  running  over  the  plates,  is  exposed  to  the  action  of  the  fire.  It  ap- 
pears that  mild  English  steel  is  more  liable  to  internal  corrosion  than 
wrought- iron.  Internal  corrosion  is  often  met  by  hanging  in  the  boilers, 
under  water,  pieces  of  zinc,  which,  as  the  weaker  metal  seem  to  be  attacked 
in  preference  to  the  iron.  In  cases  where  the  corrosion  is  from  bad 
water,  advice  should  be  sought  from  a  competent  chemist.  The  straining 
effect  due  to  change  of  temperature  is  sometimes  enough  to  produce  rup- 
ture in  a  new  boiler  when  this  is  not  properly  allowed  for  in  designing.  For 
this  reason  one  head  of  the  Lancashire  boiler  is  attached  by  an  external 
angle-iron  ring,  in  order  that  the  end  may  "breath"  outward  more  freely. 
If  we  look  at  the  head  as  strained,  a  moments  consideration  will  show  that 
it  acts  as  a  beam.  A  given  change  of  length  of  shell  compared  with 
tubes  will  cause  a  strain  which  carries  inversely  as  the  square  of  the  dis- 
tance between  the  tube  and  shell,  and  directly  as  the  thickness  of  the 
head;  or,  if  the  head  be  so  rigid  that  the  yielding  occurs  in  the  shell  in- 
stead of  the  head,  the  result  is  the  same.  If  the  strain  exceeds  the  limit 
of  elasticity  and  is  repeated  often  enough,  the  destruction  of  the  sheet  by 
grooving  is  only  a  matter  of  time.  The  United  States  law  prohibits  the 


DESIGN  AND  CONSTRUCTION  CONTINUED'  ETC.  155 

placing  of  tubes  in  externally  fired  boilers  within  3  inches  of  the  shell,  and 
this  is,  however,  more  a  precaution  against  scale  filling  this  up  solid,  than 
against  expansion.  In  our  opinion  the  flues  of  all  boilers  should  not  be 
placed  within  4  inches  of  the  shell,  when  the  heads  are  £-inch  thick,  and 
the  distance  should  be  increased  with  the  thickness  of  the  head. 

Where  there  is  a  tendency  to  work  open  the  material,  or  to  grooving,  as 
at  the  head  flanges,  and  where  there  is  no  injurious  chemical  action  of 
the  water  or  deposit,  a  tough  steel  flange  will  resist  fracture  better  than 
an  iron  one;  but  if  it  once  gets  broken  the  steel  will  go  faster  than  the 
iron  will. 

On  Steel. — Mr.  Win.  Boyd  concluded  from  experiments  made  before 
the  construction  of  the  boiler  referred  to  in  a  paper  read  at  the  Institution 
of  Mechanical  Engineers  and  afterwards  published  in  Engineering,  pages 
310  and  320,  for  April  19,  1878,  for  marine  use  as  follows: 

1.  That  steel  plates  can  be  had  of  uniform  and  reliable  material  in 
large  quantities. 

2.  The  material  is  injured  nearly  one-third,  if  in  punching,  the  die 
is  iVinch  larger  than  the  punch. 

3.  It  is  not  hurt  by  drilling. 

4.  The  quality  is  restored  by  annealing. 

5.  Drilled  holes  are  to  be  preferred. 

6.  Especial  care  is  needed  in  staying  flat  surfaces.    In  a  paper  by  Mr. 
W.  Parker,  Chief  Engineer  and  Surveyor  for  Lloyds  [Register,  vide  Engi- 
neering, for  June  7,  1878,  p.  461,  he  says  of  marine  steel  boilers: 

"Now  that  we  have  a  material  that  gives  us  a  boiler  about  30  per  cent, 
"stronger  than  an  iron  boiler  of  the  same  scantlings,  and  as  it  seems  pos- 
"sible  that  we  may  be  able  in  the  immediate  future  to  dispense  entirely 
"with  longitudinal  rivetted  seams  by  having  the  shells  rolled,  and  ao  there 
"has  also  been  a  furnace  introduced  which  can  work  at  twice  the  pressure 
"of  the  ordinary  plain  flue,  it  does  appear  to  me  that  we  have  succeeded 
"in  a  great  measure  in  removing  the  old  conditions  that  have  militated 
"against  much  higher  pressures  being  obtained,  and  that  we  appear  to  be 
"now  in  a  position  to  make  a  fresh  departure  in  the  direction  of  still 
"greater  pressures.  If  the  improvements  which  I  have  indicated,  prove, 
"as  I  have  little  doubt  they  will  prove,  successful,  we  shall  have  gained  an 
"advantage  represented  in  the  aggregate  by  an  increase  of  about  80  or  90 
"per  cent  of  the  working  pressure.  In  other  words  we  will  be  able  to 
"work  the  present  form  of  boiler  at  160  pounds  or  170  pounds  per  square 
"inch,  and  although  the  resultant  economy  will  not  be  so  great  as  that 
"which  attended  the  increase  at  one  step  from  30  pounds  to  60  pounds,  we 
"may  confidently  anticipate  that  it  will  be  sufficient  to  give  a  great  im- 
"petus  to  steam  navigation,  advancement  in  which  has  lately  been  so 
"much  retarded  by  the  high  consumption  of  fuel. " 

In  the  United  States  the  use  of  steel  is,  for  stationary  boilers,  extend- 
ing rapidly,  and  there  is  little  else  used  for  the  shells  and  fire-boxes  of 
locomotive  boilers,  though  for  stay  bolts  and  rivets,  iron  is  still  preferred; 


156  STEAM  MAKING;  OS,  BOILER  PRACTICE. 

while  for  boats  on  the  Mississippi  River,  it  is  now  much  used,  as  allowing 
higher  pressure  to  be  carried. 

We  give  some  conclusions  drawn  for  water  tube  boilers  by  one  of  the 
best  authorities,  but  they  embody  our  views  for  all  boilers. 

With  regard  to  water-tube  boilers,  Mr.  Robert  Wilson  concludes  that 
the  points  to  be  attended  to  are: 

1.  To  keep  the  joints  out  of  the  fire. 

2.  To  protect  the  furnace  tube  from  cold  air  when  the  fire-door  is 
opened. 

3.  To  provide  against  the  delivery  of  cold  feed  directly  into  the  fur- 
nace tubes. 

4.  To  provide  a  proper  circulation  to  carry  the  steam  from  the  sur- 
faces where  it  is  formed. 

5.  To  provide  passages  of  ample  size  for  the  upward  currents  of 
steam  and  water,  which  must  be  separated  from  downward  currents  of 
water. 

6.  To  provide  passages  of  ample  size  for  the  steam  and  water  be- 
tween the  various  sections  of  the  boiler  in  order  to  equalize  the  pressure 
and  water  level  in  all. 

7.  To  provide  ample  surface  for  the  steam  to  leave  the  water  quietly. 

8.  To  provide  a  sufficiently  large  reservoir  for  the  steam  to  prevent 
the  water  being  drawn  out  of  its  proper  place  by  suddenly  opening  a 
steam  or  safety-valve. 

9.  To  provide  against  the  flame  taking  a  short-cut  to  the  chimney, 
and  impinging  against  tubes  containing  steam  only. 


CIRCULATION  OF  WATER. 


A  very  important  matter  is  the  movement  of  the  mass  of  water  as  a 
whole  in  the  boiler,  caused  by  the  action  of  the  heat  and  the  formation  of 
steam.  It  has  been  said  by  good  authority,  "that  it  is  no  exaggeration  to 
"say  that  the  efficiency  and  safety  of  a  steam  boiler  depend  as  much  upon 
"the  efficiency  of  the  water  circulation,  as  they  do  upon  the  strength  and 
"disposal  of  the  material  of  the  boiler." 

In  a  plain  cylinder  boiler  we  have  a  furnace  hotter  at  one  end  than 
the  other,  hence  the  water  rises  over  the  fire  to  a  higher  level  than  it  has 
elsewhere,  and  flows  down  to  the  back  end  along  the  surface.  At  the  rear 
end  it  passes  vertically  downward  and  therefore  sends,  by  inertia,  the  solid 
matter  carried  with  it  to  the  bottom,  or  to  the  flues  where  a  greater  incrus- 
tation takes  place  than  elsewhere.  With  the  tubular  and  flue  externally 
fired  boilers,  the  hottest  part  of  the  shell,  except  directly  over  the  fire,  is 
at  the  highest  portion  exposed  to  flame,  and  as  this  surface  is  nearly  ver- 
tical, a  large  amount  of  steam  and  water  rises  close  to  the  shell,  and  if  a 
central  space  is  left  between  the  tubes  the  bulk  of  the  water  will  descend 
in  the  middle  of  the  boiler  This  has  in  one  instance  of  which  we  have 


DESIGN  AND  CONSTRUCTION  CONTINUED,  ?ETC.  157 

knowledge,  been  shown  by  the  scour  marks  of  the  sand  carried  in  the 
wate. 

The  importance  of  a  good  circulation  is  evident  from  a  purely  theoretic 
view,  for  it  is  well  known  that  the  only  limit  to  the  amount  of  heat  which 
can  be  transferred  through  an  iron  plate  from  one  fluid  to  another  is  de- 
pendent only  on  the  rate  at  which  it  can  be  taken  away  from  and  brought 
to  the  surfaces;  while  in  the  Latta  fire  engine  and  the  Herreshoff  coil 
boilers,  an  artificial  circulation  is  maintained  by  an  independent  circu- 
lating pump.  It  is  of  the  first  importance  that  in  water  tubes  of  a  larger 
diameter  than  6  inches,  the  upward  and  downward  currents  of  water 
should  be  separated,  especially  when  the  water  is  bad;  and  any  heating 
surface  near  quiet  water  is  almost  sure  to  form  scale.  In  boilers  with 
water  tubes,  one  end  of  a  tube  is  usually  at  a  higher  level  than  the  other. 
Small  water  tubes  in  large  flues,  as  in  the  Martin  boiler  once  so  largely  used 
in  the  United  States  Navy,  are  now  little  employed  except  by  Messrs.  Shand 
&  Mason,  builders  of  fire  engines  in  London;  tubes  with  one  end  closed 
hanging  from  a  sheet  above  the  flre  are  usually  fitted  with  internal  circu- 
lating tubes  down  which  the  water  flows,  while  the  steam  formed  escapes 
outside  of  the  circulating  tube.  The  same  arrangement  is  used  with  the 
Perkins  Surface  Condenser  to  bring  up  the  cold  water. 

Small  cross  tubes  as  in  the  Martin  boiler  unless  made  of  brass  were 
found  to  be  subject  to  rapid  external  corrosion,  when  the  boilers  were 
frequently  laid  off,  and  when  made  of  brass  the  expense  and  difficulty  of 
maintaining  the  joints,  and  the  impossibility  of  cleaning  soot,  have  pre- 
vented their  adoption. 

ON  HEATING  SURFACE. 

Rankine  gives  the  following  formula  and  table  based  upon  theoretic 
grounds  as  expressing  the  probable  efficiency  of  a  furnace  where  the 
ratio  of  evaporation  obtained,  Eft  to  the  theoretic  evaporation  of  the  fuel, 
E,  is  called  the  efficiency, 

E'         B  S 


E       S+AF 


where  8  =  square  feet  of  heating  surface,  and  F  =  pounds  of  fuel  burned 
per  hour.  A  =  0.5  for  chimney  draft,  and  0.3  for  forced  draft.  B  =  1  for 
best  connection,  0.917  for  ordinary  boilers  and  chimneys  and  0.95  for  or- 
dinary boilers  with  forced  draft.  He  classes: 

I.  For  boilers,  with  best          connection,  chimney  draft 

II.  "  "      ordinary          " 

III.  "  "     best  "  forced 

IV.  "  "      ordinary 


158 


STEAM  MAKING;  OR,  BOILER  PRACTICE. 


FOR  CLASS. 


s 

F 

I. 

II. 

III.                            IV. 

0.1 

0.16 

0.15 

0.25 

0.22 

0.25 

0.33 

0.31 

0.45 

0.43 

0.5 

0.50 

0.46 

0.62 

0.59 

0.75 

0.60 

0.55 

0.71 

0.68 

1.0 

0.66 

0.61 

0.77 

0.73 

0.25 

0.71 

0.65 

0.81 

0.77 

1.5 

0.75 

0.96 

0.83 

0.79 

2.0 

0.80 

0.73 

0.87 

0.83 

2.5 

0.83 

0.76 

0.89 

0.85 

3.0 

0.86 

0.79 

0.91 

0.86 

6.0 

0.92                             0.84 

0.95 

0.90 

9  0 

0.95 

0.87 

0.97 

0.92 

D.  K.  Clark  from  examination  of  boiler  trials  concludes  as  follows: 
The  water  evaporated  per  square  foot  of  grate  per  hour,  w,  when  the  fuel 
per  square  foot  of  grate,  /,  is  given  is: 

w  =  a  r2  +  b  f  where  r  —  number,  square  feet  of  heating  surface  per 
square  foot  of  grate,  and  a  and  b  are  constants  with  different  value  for  dif- 
ferent classes  of  boilers  and  fuels,  as  follows: 


FOB  ENGLISH  SOFT  COAL. 

a  — 

b  = 

For  stationery  boilers              

0.0222 

9.56 

0.016 

10.25 

For  portable  boilers                              ...             .         .         .      .... 

0.008 

8.6 

0.009 

9.7 

Locomotive,  Coke  

0.0178 

7.94 

He  says  the  rate  of  fuel  per  square  foot  of  grate  should  not  be  less  than 
given  below,  in  order  to  apply  the  above: 


6     1  10 

15 

20 

30 

40 

12.1 
11.2 
3.2 
5.2 
7.0 

50 

60 

11.7 
16 

70 

75 

80 

_90_ 

26.3 
36 

100 

Stationary  .  .  . 

.2 
.17 
.05 
.1 
.1 

.7 

.7 
2 

.'4 

1.7 
1.6 
.4 
.7 
1.0 

3. 
2.8 
.8 
1.3 
1.8 

6.8 
6.3 
1.8 
2.9 
4.0 

18.9 
17.5 
5.0 
8.1 
11.0 

15.9 
21 

18.3 
25 

20.8 
28 

32.5 
44 

Marine                         

Portable       

Locomotive,  Coal 

Locomotive,  Coke... 

DESIGN  AND  CONSTRUCTION  CONTINUED, 'ETC. 


159 


Reducing  to  the  same  basis 


--. 

S  +  AF 


Ef  =  b  + 


a  r*  _     f  b  +  a  r2 


*    =  Fb    +  ;-£-,  expressions 

Jl/  £     Hi 


which  are  radically  unlike  and  cannot  well  be  harmonized  except  that  in 
either  case  it  maybe  seen  that  the  more  heating  surface  per  pound  of  fuel 
burned  the  better  economic  performance,  while  the  latter  shows  that  a  re- 
duction of  grate  area  will  improve  the  evaporation,  as  rand  /are  increased 
together. 

This  is  true  only  within  certain  limits,  as  it  is  difficult  to  burn  more 
than  a  certain  quantity  of  coal  per  square  foot  of  grate  per  hour  without 
increase  in  the  draft. 

Of  these  two  formulae,  that  of  Clark  seems  more  nearly  to  apply  to  the 
experimental  data,  although  his  constants  meet  with  great  change.  Thus 
from  the  experiments  upon  the  Wabash  Railway  with  coal  from  Central 
Illinois,  Clark's  constants  become  for  locomotives 


b  =  4.5 


a  =  0.05 


The  proportions  of  heating  surface  per  square  foot  of  grate  is  usually 
taken  as  the  governing  element,  and  to  Chief  Engineer  Isherwood  is  due 
the  first  demonstration,  that  boilers  may  be  made  too  large  for  the  purpose 
of  economic  evaporation.  Lately  Mr.  Alfred  Blechynden  has  made  an  ex- 
tended mathematical  investigation  of  the  subject,  and  he  concludes  that 
for  land  boilers  an  efficiency  of  0.75  is  desirable,  and  for  yachts  and  boats 
intended  for  speed  without  counting  freight,  that  with  fuel  to  be  had  at 
intervals  the  desirable  efficiencies  are  as  given  below  in  the  tables: 

DESIRABLE  EFFICIENCIES  FOE  VARIOUS  PRESSURES,  AND  TIMES  BETWEEN 
COALING,  FOR  ORDINARY  MARINE  BOILERS— ORDINARY  DRAFT. 


PRESSURE. 


NUMBER  OF  DAYS  FOR  WHICH  COAL.  IS  CARRIED. 


K 

% 

« 

1 

2 

3 

4 

5 

10 

20 

60 

247 

.314 

358 

.390 

468 

.514 

547 

.571 

.642 

.704 

75  

237 

303 

.346 

.377 

456 

.502 

.535 

.559 

.631 

.695 

90  

229 

.293 

.335 

.366 

.444 

.491 

.524 

.548 

.625 

.686 

105 

221 

284 

325 

356 

.434 

.481 

.513 

.538 

.612 

.678 

120  

214 

.276 

.317 

.348 

.425 

.472 

.503 

.529 

.604 

.671 

135 

208 

.269 

309 

.339 

.416 

.463 

.495 

.521 

.596 

.668 

150... 

203 

.262 

.302 

.332 

.408 

.455 

.487 

.513 

.589 

.658 

160 


STEAM  MAKING;  OR,  BOILER  PRACTICE. 


STEAM  JET  DRAFT. 


PRESSURE. 


NUMBER  OF  DAYS  FOR  WHICH  COAL  IS  CARRIED. 


* 

% 

H 

1 

2 

3 

4 

5 

10 

20 

60  

.307 

382 

430 

464 

545 

592 

623 

646 

712 

770 

75 

295 

370 

417 

451 

5S2 

579 

612 

635 

703 

762 

90.  . 

.285 

359 

405 

439 

521 

568 

601 

625 

694 

754 

105  

276 

349 

.395 

.429 

510 

558 

590 

.615 

,685 

747 

120.  . 

268 

340 

385 

419 

500 

548 

581 

t'.i  it; 

678 

74C 

135  

,261 

332 

376 

410 

492 

539 

573 

.598 

670 

734 

150  

.255 

.324 

.369 

.402 

.484 

.531 

.565 

.590 

.664 

728 

Mr.  Blechynden's  expressions  become  too  complex  when  the  value  of 
freight  is  taken  into  account,  and  we  give  a  simpler  if  less  exact  investiga- 
tion as  an  example  of  the  method  to  be  pursued. 

Ordinary  boilers  weigh  on  board  say  40  pounds  per  square  foot  of  heat- 
ing surface,  costing  not  far  from  $4.  Allowing  for  interest  on  first  cost 
and  repairs,  together,  80  cents  per  annum,  or  20  per  cent.  Freight  per  ton 
per  working  year  may  be  assumed  as  $50,  or  $1  per  annum  per  square  foot 
of  heating  surface,  making  an  annual  cost  per  square  foot  of  heating  sur- 
face of  $1.80. 

Suppose  fuel  costs  $4  per  ton  and  the  boat  is  under  weigh  50  days 
per  year  ,then  for  each  pound  of  fuel  per  hour  burned  there  is  expended 
$2  per  year  and  the  freight  values  are,  if  fuel  is  taken  every  day,  $1.20.  If 
freight  can  be  taken  on  board  every  hour  the  average  values  may  be  taken 
as  half  that  given  or  60  cents  in  place  of  $1.20. 

Suppose  that  from  the  engine  power  desired  we  know  that  we  have  to 
evaporate  20,000  pounds  of  water  per  hour  we  make  out  the  following  table 
by  the  aid  of  the  Eankine  formula  reversed: 

EV       A       Tfl 

S  =     TZT'  taking  A  =  J,   B  -  0.9 


we  have  then  t. 

t  _      10000 

13.0  —  E? 

:*i 

SH 

<M    00    S 

|o|| 

O^                    ty  a, 
^OB                     C  S 

U 

|£ 

C6    j 

-    = 
£H    2l 

fl^-i  O 
.0  0  O 

**  ca      fl 

§>•                    OS  ^ 

IS 

'g-o 

ii 

§33  §» 

£~02  -2 

°-O 

O-=  3 

*o  3 
S  e8 

M° 

§T3 

!f*J 

*li 

OOs 

•~    §§ 
lIsSl 

ill 

flt 

oo, 

11 

ill 

C(Z    S 

5'S 

H 

o 

0 

QB 

6"" 

£ 

3 

1000 

1800 

6667 

13333 

15133 

4000 

19133 

4 

1111 

2000 

5000 

10000 

12000 

3000 

15000 

5 

1250 

2250 

4000 

8000 

10250 

2400 

12650 

6 

1428 

2580 

3333 

6667 

9247 

2000 

11247 

7 

1667 

3000 

2860 

5718 

8718 

1715 

10433 

8 

2000 

3600 

2500 

5000 

8600 

1500 

10100 

9 

2500 

4500 

2222 

4444 

8944 

1333 

10277 

10 

3333 

6000 

2000 

4000 

10000 

1200 

11200 

11 

5000 

9000 

1818 

3636 

12636 

1111 

13747 

12 

10000 

18000 

1667 

3333 

21333 

1000 

22333 

DESIGN  A^'D  CONSTRUCTION  CONTINUED,  ETC. 


161 


If  the  evaporative  efficiency  of  the  fuel  is  not  so  high  E  is  lessened  and 


we  have  different  values.    If  E  =12  we  have    S 
with  columns: 


10000 
11— 


and  our  table 


Evaporation  in 
pounds  of  wa- 
ter per  pound 
of  coal. 

No.  square  feet 
of  h  eating  sur- 
face required. 

Cost  in  dollars 
per  year  of 
interest  and 
freight  on  boi- 
ler. 

o.S 

If. 

o 

tc-o 

TJ  QJ 

1 

d'o'ft 

Sum  of  columns 
three  and  live. 

If 
J| 

jo  <-i'c8 

"™«2  8 

Sum  of  columns 
six  and  seven. 

5 
6 
7 
8 
9 
10 

1667 
2000 
2500 
3333 
5000 
10000 

3000 
3600 
4500 
6000 
9000 
18000 

4000 
3333 
,2860 
'2500 
2222 
2000 

8000 
6667 
5720 
5000 
4444 
4000 

11000 
10267 
10220 
11000 
13444 
22000 

2400  ' 
2000 
1715 
1500 
1333 
1200 

13400 
12267 
11935 
12500 
14777 
23200 

If  the  -type  of  boiler  used  weighs  more  or  less  than  40  pounds  per 
square  foot  of  heating  surface,  column  three  may  be  varied  accordingly.  If 
the  boiler  is  to  be  in  full  steam  for  more  or  less  than  50  days  in  the  year 
or  fuel  costs  more  or  less  than  $4  per  ton,  column  five  is  to  be  varied  ac- 
cordingly. Column  six  will  do  for  land  boilers.  If  the  coal  is  be  carried  for 
more  or  less  than  one  day,  column  seven  is  to  be  varied  and  from  the  sum 
we  easily  find  the  proper  heating  surface.  The  real  quantity  of  water  to 
be  evaporated  is  not  essential  as  all  the  quantities  in  the  table  will  vary 
therewith  also. 

If  instead  of  freight  charges  we  take  the  value  of  land  occupied,  and  if 
fuel  has  to  be  stored,  the  room  it  occupies,  we  shall  see  that  there  is  not 
perhaps,  so  great  a  difference  between  steamboat  and  stationary  boilers  as 
was  supposed  by  Mr.  Blechynden.  And  from  the  table  we  can  see  that  the 
real  element  is  the  time  per  year  the  boilers  are  to  be  at  work.  In  a  flour 
mill  running  144  hours  per  week  for  instance,  a  high  economic  performance 
is  very  desirable,  but  for  a  water  works  with  storage  reservoir  where  one 
day's  pumping  in  a  week  will  keep  up  the  supply  and  fuel  is  obtained  as 
wanted,  an  evaporation  over  seven  or  eight  is  not  desirable  until  the  work 
is  increased.  The  Western  Kiver  Steamboat  Boiler  is  thus  seen  to  be  ad- 
mirably adapted  to  the  conditions  in  which  it  works,  while  for  an  ocean 
line  steamer  it  would  be  out  of  place. 

The  kind  of  boiler  to  be  selected  for  any  particular  work  or  locality  de- 
pends upon  many  things,  and  it  is  seldom  advisable  to  make  very  wide  de- 
partures from  the  common  practice  around  the  given  locality.  Thus  with  well 
water,  locomotives  in  Central  Ohio  sometimes  have  to  have  their  tubes  re- 
newed every  six  months  on  account  of  scale  and  consequent  burning  of 
ends.  It  would  not  be  advisable  to  put  in  a  locomotive  type  boiler  for  a 
flour  mill  in  this  region  and  you  will  find  few  tubular  boilers  there.  The 
flue  return,  externally  fired  type,  or  the  French  type  is  suitable,  although 
the  latter  have  been  little  used  in  this  country.  The  externally  fired  re- 


162  STEAM  MAKING;  OR,  BOILER  PRACTICE. 


turn  tube  type  is  common  with  good  water,  while  the  Cornish  and  Lan- 
cashire are  almost  unknown  and  from  their  cost  and  the  higher  pressures 
used  are  not  likely  to  become  favorites  with  the  United  States. 

For  hard  steady  work  where  land  is  worth  little  the  single  cylinder  type 
has  many  good  points.  For  high  pressures  the  water  tube  type  is  in  many 
places  a  favorite.  The  internally  fired  boilers  of  the  locomotive  type  usu- 
ally give  high  evaporative  results  but  are  hard  to  keep  clean. 

The  externally  fired  return  tubular  with  central  gangway  seems  to 
combine  more  good  features  for  less  money  than  many  other  types  and 
without  the  gangway  is  probably  more  used  in  the  United  States  than  any 
other.  With  two  to  five  flues  is  the  standard  river  practice  for  the  Missis- 
sippi and  tributaries. 

The  choice  of  marine  types  is  governed  by  the  room  at  disposal  as  to 
whether  a  single  or  double  fire  room  can  be  had. 

A  properly  constructed  boiler  requires  a  very  great  internal  pressure 
to  burst  it.  A  36-inch  shell  £  inch  thick  and  10  feet  long,  with  ordinary 
rivetting,  has  18  square  inches  of  metal,  which  requires  at  least  50,000 
pounds  per  square  inch,  tensile  strength,  in  all  450  tons,  or  416  pounds  per 
square  inch  to  burst  it;  and  by  the  United  States  Law  is  allowed  125  pounds 
per  square  inch  pressure;  or  on  a  tow  boat  on  the  Mississippi  Kiver  a 
pressure  of  175  pounds  to  the  square  inch. 

With  this  margin  of  strength  the  occurrence  of  violent  explosions  has 
been  taken  to  justify  the  hypothesis  of  some  violent  internal  action,  and  as 
there  are  probably  more  cases  of  quiet  failure  than  of  violent  explosion, 
there  has  seemed  a  certain  probability  in  this  view.  A  simple  rupture  at- 
tended by  the  loss  of  steam  and  water  under  ordinary  working  can  occur 
only  from  a  purely  local  failure  of  a  seam,  or  rivet,  either  from  original 
defect  in  material  or  manufacture,  or  from  subsequent  injury,  and  sucb 
cases  seldom  attract  public  attention. 

The  failure  of  boilers,  whether  violent  or  quiet,  has  been  attributed  to 
steadily  accumulated  pressure;  steam  formed  from  sudden  contact  of 
water  with  red  hot  metal;  electrical  action;  the  decomposition  of  water 
or  steam  into  hydrogen  and  oxygen,  etc.  Let  us  first  consider  overheat- 
ing. Although  it  is  possible  for  boilers  to  be  exploded  in  consequence  of 
the  formation  of  steam  by  the  contact  of  water  with  very  hot  plates,  yet 
overheating  cannot  be  taken  as  the  only  cause,  or  even  the  general  one,  of 
explosions,  for  there  is  too  much  evidence  that  boilers  do  explode  with 
plenty  of  water  in  them.  Burnt  iron  is  easily  recognized  and  its  absence 
is  good  evidence  of  a  sufficient  quantity  of  water. 

Admitting  the  case  of  overheating,  it  is  doubtful  whether  the  formation 
of  steam  would  cause  an  explosion,  for  the  actual  quantity  of  heat  which  the 
metal  can  hold  is  not  capable  of  very  much  work  in  the  way  of  generating 
steam,  as  may  be  best  seen  by  an  example  computed  by  the  aid  of  our 
table  of  the  properties  of  steam.  Suppose  a  boiler  with  a  water  space  of 
100  cubic  feet  and  a  steam  space  of  4.0  cubic  feet  becomes  short  of  water, 
and  by  reducing  the  water  to  90  cubic  feet,  increasing  of  course  the  steam 
space  to  50  cubic  feet,  a  surface  of  100  square  feet  of  £-inch  plate  weighing 


DESIGN  AND  CONSTRUCTION  CONTINUED* ETC.  163 

1,000  pounds  is  uncovered;  that  the  steam  pressure  is  100  pounds  per  square 
inch,  and  that  the  iron  plates  uncovered  rise  to  1,000°  F.  hotter  than  the 
steam  and  water,  or  to  1,338°  F.,  what  will  be  the  consequence  of  pumping 
in  10  cubic  feet  of  water  at  100°  F.  in  five  minutes? 

The  condition  of  things  at  first  is:  90  cubic  feet  of  water  at  say  60  pounds, 
is  5,400  pounds  of  water  x  308  units  =  1663200  units;  50  cubic  feet  steam  x 
density  0.263=13.15  pounds;  13.15  poundsx  1184  units  =  15570;  total  1678770. 
The  heat  stored  in  the  hot  iron  is  at  best  1000  pounds  x  1000°  x  0.111  the 
specific  heat,  or  say  111000  units.  If  this  were  all  to  be  put  into  the  steam 
it  would  superheat  it  to  a  very  great  degree  and  undoubtedly  raise  the 
pressure  beyond  the  bursting  pressure.  Let  us  examine  this  by  steps,  first 
supposing  no  fresh  water  to  have  been  added,  and  that  the  pressure  has 
raised  to  110  pounds.  At  that  time  there  will  be  present  as  steam 

Units. 

50  X  0.284  =  14.2  pounds,  and  its  heat  at  1186  units  is 16841 

The  5,400  pounds  of  water  is  now  at  344°  F.  and  the  heat  is  315  units 1701000 

11 17841 
Formerly , ...1678770 

So  there  has  been  added  from  the  iron ...  .    39071 


If,  however,  the  10  cubic  feet  of  water  have  all  been  pumped  in,  the  account 
will  be  very  different.    At  110  pounds  we  have  40  cubic  feet  of  steam, 


40  X  0.284  =  11.36  pounds  at  1186  units  will  give. 
6000  pounds  of  water  at  315 


Deduct  COO  pounds  of  water  feed  from  32°  to  100°,  not  furnished  600  X 
Originally 


72900 

being  in  excess  of  that  stored  in  the  iron,  say  70  per  cent,  showing  that  a  rise 
of  pressure  in  five  minutes  of  over  six  pounds  to  seven  pounds  is  not  at  all 
likely.  It  has,  however,  been  taken  that  there  was  no  heat  from  the  outsid£ 
coming  in,  and  this  is  not  likely  to  happen;  still  this  also  fairly  represents 
the  case  when  an  engine  is  at  work  and  the  fire  is  in  such  condition  that 
the  regular  supply  of  heat  is  just  enough  to  furnish  steam  for  the  engine. 
Suppose  the  engine  is  using  1,000  horse-power  with  3,600  pounds  of  water 
an  hour,  in  five  minutes  it  will  use  300  pounds,  and  the  regular  heat  from 
the  fire  is  to  be  estimated  1184  —  68  units  =  1116  units  x  300  pounds  = 
334800,  which  if  added  to  our  111000  stored  makes  up  i49000  units  or  enough 
to  raise  the  pressure  to  say  140  pounds  if  the  boiler  has  no  outlet.  Let  us 
examine  it.  At  140  pounds  we  have 


164  STEAM  MAKING;  OR,  BOILER  PRACTICE. 

Units. 

40  X  0.348  =  13.92  pounds  of  steam  at  1191  units 16589 

6000  pounds  of  water  at  331  units 1986000 

2002589 
Deduct  as  before  not  furnished 40800 

19C1789 
1678770 

283019 
\ 

which  is  less  than  the  supply  4=49000  and  the  pressure  will  rise  higher.  Let 
us  try  it  at  180  pounds: 

Units. 

Steam  40  X  0.433  =  17.32  pounds  of  steam  at  1197 20733 

6000  pounds  of  water  at  351 2106000 

2126733 
Less  as  before 40800 

20859?3 
Original^ 1678770 

407163 

Being  nearly  the  amount  at  hand,  the  pressure  will  go  above  this  point  a 
few  pounds,  and  is  undoubtedly  a  dangerous  pressure  on  an  old  or  weak- 
ened boiler,  but  could  not  be  reached  with  a  proper  and  effective  safety- 
valve  in  operation. 

We  will  next  consider  the  question  of  electrical  action  which  is  often 
brought  forward,  supported  by  the  Armstrong  generator.  Faraday  found 
in  his  examination  of  Armstrong's  apparatus  that  the  boiler  had  to  be  insu- 
lated, the  steam  wet  and  the  nozzles  of  boxwood.  He  concluded  that  the 
production  of  electricity  was  not  due  to  any  change  of  state  of  the  liquid  in 
the  boiler,  and  that  the  same  results  could  be  obtained  by  moist  com- 
pressed air.  Without  going  further  we  can  say  no  one  has  shown  how  a  boil- 
er can  be  exploded  even  by  any  quantity  of  electricity  even  if  it  wrere  there, 
as  with  the  excellent  conduction  of  the  quantities  of  iron  around  it  anything 
like  a  sudden  discharge  would  be  impossible.  We  will  leave  this  theory 
to  those  who  prefer  mystery,  and  who  are  ready  to  see  in  electric  action  a 
cause  rather  than  an  effect  of  things  not  otherwise  explained. 

The  decomposition  of  steam  into  hydrogen  by  the  absorption  of  oxygen 
by  red  hot  iron  is  an  experiment  which  requires  very  different  conditions 
from  the  ordinary  working  of  a  boiler,  and  even  granted  that  we  had  a 
boiler  full  of  water  and  hydrogen  gas  under  pressure  we  do  not  see  how  any 
amount  of  air  containing  the  fresh  oxygen  necessary  for  any  explosion  could 
be  introduced.  We  might  as  well  expect  an  ordinary  gas  holder  to  explode 
from  the  same  cause.  We  conclude  then  that  decomposition  can  not  occur  in 
the  ordinary  working  of  a  boiler,  and  if  it  did  no  explosion  would  follow  un- 
less mixed  with  oxygen,  and  if  so  mixed  in  the  presence  of  steam  no  combus  - 
tion  could  take  place,  and  if  no  steam  were  present  we  might  expect  only  a 
quiet  combustion  as  the  air  was  forced  in,  the  ignition  coming  from  some 
red  hot  plate.  A  piece  of  burnt  iron  is  evidence  of  shortness  of  water  and 


DESIGN  AND  CONSTRUCTION  CONTINUED'ETC. 


of  a  weakening  action  upon  the  metal  without  any  gas  explosion  being  re- 
quired. We  may  now  pass  to  what  is  called  over -pressure. 

Any  pressure  greater  than  the  safe  working  pressure  upon  a  boiler 
is  an  over-pressure,  and  the  result  may  be  rupture  with  or  without  an 
explosion.  The  action  of  corrosion  in  reducing  the  thickness  and  of 
change  of  form  by  change  of  temperature  in  producing  strain  upon  the 
metal,  tend  to  reduce  the  bursting  pressure  and  in  many  explosions  the 
plates  are  found  not  more  than  3^  inch  in  thickness.  Mr.  Kobert 
Wilson  states  that  it  is  possible  to  make  a  boiler  which  would  be  tight  with 
100  pounds  hydrostatic  pressure  but  that  would  explode  with  30  pounds 
steam  pressure,  or  which  in  other  words  would  almost  tear  itself  to  pieces 
when  a  portion  was  heated  to  300°  F.,  or  to  a  greater  temperature  than  some 
other  portion. 

The  operations  which  occur  very  rapidly  after  each  other  during  an 
explosion  are  probably  as  follows: 

1.  The  rupture  under  a  pressure  not  much  greater  than  the  working 
pressure  of  some  defective  portion  of  the  boiler. 

2.  The  extension  of  this  rent  through    some  adjacent  portion  of  the 
boiler,  owing  to  a  transference  of  strain,  or  by  otherwise  yielding  to  a 
shock. 

3.  The  lowering  of  pressure  caused  by  the  escape  of  fluid  from  the 
boiler  and  the  sudden  generation  of  steam  at  the  lower  pressure,  causing  a 
following  up  of  the  pressure  upon  the  moving  pieces  thereby  causing  the 
violent  characteristics  which  may  take  place. 

4.  The  ejection  in  whole  or  part  of  the  water  contained  in  the  boiler 
mixed  with  steam  formed  from  the  hot  water,  of  which,  of  course,  only  a 
small  portion  can  be  vaporized  by  the  heat  contained  in  the  water,  as  965 
units  are  required  to  boil  water  from  and  at  112°  while  at  140  pounds  the 
temperature  is  361°  or  149°  units  higher  than  212°— 965  divided  by  149  is  6} 
nearly.     That  is  to  say,  of  every  6£  pounds  of  water  in  the  boiler  one  pound 
will  be  thrown  into  steam  at  atmospheric  pressure,  while  5£  pounds  will  re- 
main as  water  either  in  the  boiler  or  more  likely  scattered  in  the  air  mixed 
with  the  steam  resulting.  In  general  all  our  knowledge  of  boiler  explosions 
goes  to  show  that  in  most  cases  the  explosion  results  from  some  defect 
either  original  or  produced,  either  visible  or  concealed  in  the  materials, 
workmanship,  or  design  and  construction  of  the  boiler.  Probably  less  than 
one  per  cent,  of  the  boilers  made  explode,  but  many  more  are  ready  to  fail 
either  quietly  or  violently  from  causes  which  may  be  easily  discovered  by 
competent  inspection. 

Some  valuable  experiments  were  made  in  1870  at  Sandy  Hook,  by  Mr. 
Francis  B.  Stevens,  of  Hoboken,  at  the  expense  of  the  united  Railroads  of 
New  Jersey.  Several  old  boilers  had  been  taken  out  of  steamers  belonging 
to  the  united  companies  and  were  burst  by  hydrostatic  pressure  and  re- 
paired and  again  burst  several  times,  finally  leaving  them  much  stronger 
than  when  taken  from  the  boafs.  Professor  E.  H.  Thurston,  of  the  Stevens' 
Institute  of  Technology,  gives  an  account  of  the  experiments,  which  we 
here  sum  up.  The  boilers  after  this  process  of  finding  out  the  weak  places 


166  STEAM  MAKING;  OR,  BOILER  PRACTICE. 

were  set  up  at  Sandy  Hook  at  the  entrance  of  New  York  Harbor,  and  three 
of  the  boilers  were  burst  as  follows: 

The  first  was  a  fire  box  boiler  28  feet  long  with  shell  6  feet  6  inches  di- 
ameter and  barrel  20  feet  4  inches  long.  The  two  furnaces  were  7  feet  long 
with  flat  arches  and  with  4  inch  water  space  all  around  and  water  leg  between 
the  furnaces.  The  products  of  combustion  passed  through  a  throat  to  a 
combustion  chamber  19  inches  long,  and  then  through  10  flues  of  which  two 
were  16  inches  and  the  other  eight  9  inches  in  diameter  and  15  feet  9  inches 
long.  The  back  connection  was  32  inches  in  length  with  a  4  inch  water 
space  behind  it.  The  return  tubes  above  were  12  in  number  and  8|  inches  in 
diameter,  and  22  feet  long  to  the  smoke  connection,  which  formed  the  base 
of  the  stack  2  feet  8  inches  in  diameter  surrounded  by  a  steam  chimney  4 
feet  in  diameter  and  10  feet  10  inches  above  the  shell  of  the  boiler.  The 
grate  area  was  38£  square  feet  and  the  total  heating  surface  was  1,350  square 
feet;  the  flat  surfaces  were  stayed  with  screw  bolts  at  7  inch  centers.  This 
boiler  was  one  of  a  pair  built  in  1856  and  had  been  13  years  in  service,  the 
last  inspection  certificate  allowed  40  pounds  pressure.  In  September  of  1871 
this  boiler  had  been  tested  by  hydrostatic  pressure  to  66  pounds  pressure, 
when  one  of  the  stay  bolts  pulled  through;  after  repairs  it  was  tested  to  82 
pounds,  and  afterwards  steam  of  60  pounds  had  been  made  in  it.  On  No- 
vember 22,  1871,  the  water  standing  12  inches  over  the  flues  a  heavy  wood 
fire  was  made  in  the  furnaces  and  steam  raised  to  50  pounds  when  the  party 
retired  to  the  gauges,  a  distance  of  250  feet  behind  screens;  at  90  pounds 
leakage  occurred,  and  at  93  pounds  the  connection  between  the  shell  and 
dome  or  steam  chimney  failed  on  the  top  of  the  shell  and  the  steam  pass- 
ing off  the  pressure  failed,  and  no  explosion  took  place. 

The  next  experiment  was  made  with  a  small  flat  stayed  box  6  feet  long, 

4  feet  high  and  4  inches  thick  made  of  two  sheets  of  /g  inch  "best  flange  fire 
box  iron"  from  the  Abbot  Iron  Company.    The  edges  were  ri vetted  through 
a  bar  with  f  inch  rivets  2  inch  centers,  the  stay  bolts  were  8|  inches  long, 
9^  inch  centers  with  the  ends  slightly  rivetted  over.    It  had  carried  138 
pounds  hydrostatic  pressure  without  difficulty.     It  was  set  on  edge  in 
brickwork  and  was  about  |  full  of  water.    The  pressure  rose  in  33  minutes 
from  0  to  167  pounds  when  a  violent  explosion  took  place,  the  bolts  pulling 
through  the  plates  without  injury  to  the  threads. 

The  next  day  a  rectangular  boiler  was  tested,  15  feet  5  inches  long,  12  feet 
2  inches  wide  and  8  feet  6  inches  high,  for  half  the  length  from  the  front,  and 
a  foot  less  for  the  remainder.  The  furnace  and  combustion  chamber  ex- 
tended 14  feet  8  inches  to  the  rear  of  the  back  connection  and  was  11  feet 

5  inches  wide.    The  back  connection  was  18  inches  in  length  and  the  tubes 
were  12  feet  in  length  to  the  smoke  connection,  2  inches  in  diameter  and  384 
in  number.   The  water  legs  were  stayed  by  1  inch  screw  bolts  12  inches  by 
8-inch  centers.     The  sides  and  ends  by  ties,  1|  rods  28  inches,  by  12  inch 
centers.  The  furnace  crown  and  top  by  "crow  foot  bars"  £  inch  by  2  inches, 
12  inch  by  17  inch  centers.   The  shell  was  of  No.  3  iron  single  rivetted  and 
there  was  a  dome  in  the  middle  of  the  top  6  feet  in  diameter  and  8  feet  8 
inches  in  height.     This  boiler  was  built  in  1845  and  after  a  service  of  25 


DESIGN  A ND  VON8TR  UCTION  CONTINUED,  &TC.  1 67 

years  was  taken  out.  The  last  inspection  allowed  a  pressure  of  30  pounds. 
Forty-two  pounds  of  water  pressure  broke  a  crown  brace  and  at  60  pounds 
12  of  these  braces  failed;  after  repairs  it  carried  59  pounds  of  water  and  45 
pounds  of  steam  safely.  The  furnace  was  filled  with  as  much  wood  as 
would  burn  freely  and  the  pressure  rose  in  13  minutes  from  29£  pounds  to 
53£  pounds,  when  it  burst  with  a  violent  explosion,  the  boiler  being  torn 
in  many  places,  the  dome  rising  to  above  200  feet  in  the  air  and  to  a  dis- 
tance of  450  feet. 

The  conclusions  reached  by  Professor  Thurston  are  for  stay  bolts  the 
greatest  distance  from  centre  to  centre  in  inches  should  be  365  times  the 
thickness  of  plates  divided  by  th  j  square  root  of  the  pressure.  The  latter 
should  be  multiplied  by  the  factor  of  safety  desired,  which  in  this  case 
should  not  be  less  than  6.  (The  United  States  Navy  use  8.)  The  diameter 
of  screw  bolts  should  be  twice  the  thickness  of  the  sheet  with  £  inch  added. 
The  conclusions  drawn  are  as  follows: 

1.  A  violent  explosion  may  take  place  in  a  boiler  when  there  is  plenty 
of  water  in  it. 

2.  A  moderate  pressure  of  steam  may  produce  a  terrific  explosion 
when  there  is  plenty  of  water. 

3.  That  a  boiler  may  explode  under  steam  at  a  less  pressure  than  it 
has  stood  from  water  pressure  without  apparent  injury. 

The  above  conclusions  are  not  new  but  this  was  the  first  experimental 
demonstration  of  them,  though  the  first  and  third  had  been  proved  by 
facts. 

We  add  to  these  a  fourth,  which  is:  A  rupture  will  be  followed  by  re- 
lief of  pressure  with  or  without  explosion  as  the  fracture  is  extended  or 
restricted. 

Implicit  confidence  cannot  be  placed  in  the  hydrostatic  pressure  test, 
but  it  should  be  followed  with  careful  inspection  assisted  by  the  sound  of 
a  blow  struck  with  alight  hammer.  Many  boilers  have  exploded  when  cor- 
rosion has  reduced  the  metal  to  such  a  thickness  that  a  smart  blow  from  a 
round-ended  hammer  would  have  gone  through  the  sheet,  while  the  boiler 
has  shown  tight  when  under  hydrostatic  pressure. 


CHAPTER     VIM. 

MISCELLANEOUS   BOILEBS.-CHOICE  OF  BOILER  FITTINGS   AND  APPUR- 
TENANCES. 

As  we  have  seen,  each  type  of  boiler  has  its  distinctive  features.  Those 
with  large  grates  are  suited  for  a  class  of  fuel  which  requires  air  in  close 
contact,  and  room  for  evaporation  of  the  water  which  is  contained  therein — 
the  grate  bars  are  often  replaced  by  a  plate  with  or  without  perforations. 
Sawdust  and  fine  chips  or  shavings  are  burned  on  a  close  plate.  Wet  fuel 
requires  room  and  is  usually  some  kind  of  refuse  which  is  to  be  got  for 
low  cost.  Crushed  sugar  cane  refuse,  or  "bagasse, "  was  probably  the  first  ex- 
ample of  this  kind,  for  the  saw-mill  furnaces  were  more  generally  fired  with 
edgings  and  slabs  than  with  sawdust.  Spent  tanbark  has  been  used  in  the 
tanneries,and  much  time  and  money  has  been  spent  in  improvement. 

The  most  common  refuse  fuel  is  that  from  the  thrashing  machine— be- 
ing the  chaff  after  removal  of  the  grain.  These  machines  are  usually 
driven  by  a  portable  engine,  and  the  fuel  is  often  mixed. 

Refuse  coal  is  also  a  fuel  which  engages  a  great  deal  of  attention,  and 
thus  very  many  attempts  have  been  made  to  devise  a  furnace  for  universal 
use.  With  soft  coal  little  trouble  is  met  with  except  from  the  earthy  matter 
and  clinkers,  the  latter  are  a  nuisance  and  require  some  trouble  in  manage- 
ment. Coke  dust,  or  "breeze, "  burns  well  with  a  forced  draft,  and  refuse 
anthracite,  if  burned  with  a  moderate  rate  of  combustion  if  not  disturbed, 
burns  well  for  a  certain  time.  The  removal  of  ash  and  earthy  matter  makes 
it  difficult  to  keep  up  the  fire. 

Large  flues  are  required  for  fuel  which  has  an  excess  of  hydro-carbon 
in  order  to  keep  the  gas  from  getting  chilled,  and  to  give  time  for  com- 
bustion. Small  flues  require  constant  care  to  keep  them  from  silting  or 
sooting  up.  With  a  strong  draft  less  trouble  is  experienced,  but  with  good 
proportions,  and  an  anthracite  fire,  flues  need  not  be  swept  oftener  than 
once  a  week,  while  with  the  poorer  kinds  of  western  coal,  and  the  same 
boiler,  once  in  twenty-four  hours  would  not  be  excessive  care. 

The  water  circulation,  steam  and  water  room  have  all  their  influence 
in  affecting  the  durability  of  the  boiler,  and  many  forms  of  boilers  which 
have  been  successful  in  a  few  isolated  cases,  or  even  in  many  cases,  con- 
fined to  one  locality  would,  if  erected  in  different  circumstances,  prove  an 
entire  failure. 

The  quality  of  the  water, — the  character  of  material  held  in  suspension 
and  solution,  is  one  of  the  most  important  factors  in  making  choice  of  a 
boiler,  as  also  the  usage,  whether  constant  or  intermittent,  and  whether 
uniform  or  varied,  while  it  is  at  work.  The  opportunities  afforded  for  ex- 
amination and  cleaning  are  also  to  be  considered. 


MISCELLANEOUS  BOILERS,  ETC.     '  169 

It  is  thus  evident  that  we  shall  meet  many  cases  where  a  particular 
type  of  boiler  has  been  successful  in  isolated  examples,  and  even  where 
many  boilers  of  a  given  type  are  working  to  satisfaction,  within  a  definite 
boundary,  which  would  not  bear  transportation  beyond  that  boundary. 
Heretofore  we  have  confined  ourselves  to  the  general  types  of  boilers  and 
with  enough  of  comment  to  show  the  special  fitness  for  certain  uses. 

We  have  seen  that  with  regard  to  evaporation  that  both  in  econo- 
my and  capacity  the  results  were  governed  entirely  by  the  magnitude  of 
the  heating  surface,  the  amount  and  intensity  of  the  fuel  burned  and  the 
quality  and  kind  of  fuel,  and  not  to  any  extent  by  the  disposition  of  the 
material  of  the  boiler  and  furnace  further  than  it  affects  the  more  or  less 
complete  process  of  combustion.  And  that  so  long  as  ordinary  care  is 
taken  to  maintain  the  combustion  arrangements  in  a  state  of  efficiency  one 
boiler  is  as  good  as  another  and  a  choice  must  be  made  on  the  other  con- 
siderations. 

1. — The  Fuel. — If  anthracite  is  used,  a  grate  area  for  burning  from  6  to 
20  pounds  of  coal  per  square  foot  per  hour  must  be  provided  for  a  stationary 
boiler,  and  from  12  to  30  pounds  for  a  marine  boiler.  For  a  locomotive 
from  30  to  100  pounds — the  former  being  a  rate  found  with  slack  and  waste 
on  the  Philadelphia  &  Heading  Road,  while  the  latter  is  reache  1  by  pass- 
enger engines.  About  300  pounds  per  square  foot  of  grate  seems  to  be  a 
limit  to  the  duration  of  the  fire,  at  the  expiration  of  which  it  has  to  be  re- 
newed; but  with  anthracite  renewal  means  rebuilding  after  that  time,  and 
if  fuel  is  added  during  the  time  in  question  its  effect  is  commonly  to  put 
out  what  has  been  burning  without  getting  ignited  itself.  Any  attempt  to 
clean  the  fire  with  a  rake  or  slice  bar  usually  puts  it  out.  The  more  there 
is  than  20  to  25  pounds  per  square  foot  of  grate  per  hour  burning  the  more 
certain  are  these  results. 

&o  much  for  the  grate  required  for  anthracite.  The  size  of  flues,  tubes, 
and  arrangement  of  furnace  is  a  matter  of  indifference,  save  that  the  area 
through  the  flues  is  usually  taken  as  f  to  ^  of  the  grate;  with  a  forced  draft 
this  may  be  diminished  without  interfering  with  the  capacity  while  the 
economy  may  be  increased,  or  if  it  be  enlarged,  the  economy  remaining 
the  same,  the  capacity  may  be  increased. 

With  good  bituminous  coal  the  flues  are  often  slightly  increased,  and 
more  room  is  required  in  the  furnace, — the  rates  of  combustion  may  be 
considered  as  50  per  cent,  in  excess  of  those  for  anthracite.  As  the  quality 
of  the  fuel  deteriorates,  more  room  and  more  grate  are  required.  Mixtures 
of  fuel  often  produce  excellent  results — anthracite  and  bituminous  coal, 
coal  and  wood,  soft  and  hard  wood,  etc.  In  any  case  care  must  be  taken 
with  the  arrangement  of  the  furnace  in  such  a  manner  that  no  portion  of 
the  metal  of  the  boiler  shall  become  locally  much  hotter  than  the  balance 
of  the  boiler,  to  avoid  the  straining  and  risk  of  burning  the  metal  pro- 
duced thereby. 

2.— The  Quality  of  the  Water.— Many  substances  held  in  solution  or 
suspension  in  hot  water  are  deleterious  to  the  metal  of  the  boiler.  Some 
are  actually  corrosive,  some  are  merely  productive  of  scale  which  may  hide 


170 


STEAM  MAKING;    OR,  BOILER  PRACTICE. 


OGLE'S     BOILER. 


, 


MISCELLANEOUS  BOILERS,  ETC.  171 

corrosion  or  may,  if  of  sufficient  thickness,  cause  the  metal  of  the  boiler 
to  become  overheated.  Some  substances  which  are  soluble  in  water  at 
ordinary  temperatures  and  even  at  212°  F.  are  insoluble  in  water  at  higher 
temperatures  and  are,  of  course,  precipitated  in  fine  powder,  this  pow- 
der falls  to  the  bottom  in  quiet  water,  but  is  kept  in  suspension  and  rises 
to  the  surface  in  places  where  it  is  sufficiently  agitated.  New  combinations 
are  often  formed  with  the  mere  dirt  which  has  been  there  all  the  time  in 
mechanical  suspension.  Oil  and  grease  returned  from  the  engines  by  an 
open -heater  or  a  condenser  is  a  new  element,  especially  at  high  tempera- 
rures.  Sulphate  of  lime  is  actually  less  soluble  in  water  of  high  tempera- 
ture, and  at  50  pounds  pressure  above  the  atmosphere  is  entirely  insoluble. 
Carbonate  of  lime  held  in  solution  in  water  containing  carbonic  acid  and 
bi- carbonate  of  lime  deposit  carbonate  of  lime  as  the  temperature  of 
the  water  rises  by  driving  out  the  carbonic  acid  and  by  separating  into 
carbonate  of  lime. 

These  two  substances  form  the  basis  of  most  kinds  of  scale, — a 
third  being  simply  earthy  or  sandy  matter  met  with  in  the  water. 
If  the  ebullition  be  strong  enough  to  keep  most  of  this  deposit  in  suspen- 
sion at  or  near  the  top  of  the  water,  it  may  be  removed  by  a  surface 
blower;  or  if  a  closed  feed  heater  be  used  the  feed  water  may  be  raised  by 
the  use  of  live  steam  nearly  to  the  temperature  of  the  boiler  and  the  de- 
posit allowed  to  settle  to  the  bottom  or  other  surface  of  the  heater  and  re- 
moved by  blowing  or  washing  out.  Care  should  be  taken  to  wash  out  with 
warm  water  if  possible. 

It  would  seem  at  first  sight  that  distilled  water  as  the  return  water 
from  a  building  heated  by  steam  or  by  a  surface  condenser  would  be  ex- 
actly what  was  required,  but  in  either  case  the  air  which  will  enter  the 
pipes  when  the  pressure  falls  below  the  atmosphere  induces  pitting,  and 
unless  the  cylinder  oil  b  3  mineral,  even  at  ordinary  pressures,  we  find  that 
it  decomposes  and  fatty  acids  are  formed,  which  act  very  rapidly. 

With  the  purification  of  water  before  usage  we  have  little  to  do.  By 
the  addition  of  quicklime  many  evils  are  removed,  but  in  most  cases  noth- 
ing can  be  done.  We  have  then  after  considering  the  water  to  determine 
what  may  be  done.  If  the  water  contain  only  a  small  portion  of  impurity, 
which  will  form  scale,  almost  any  imagined  form  of  boiler  may  be  success- 
fully used. 

We  have  known  instances  where  locomotives  fed  with  surface  water  in 
rocky  districts  in  New  England  have  run  for  twenty  years  without  having 
a  tube  removed,  while  in  central  Ohio  there  are  regions  in  which  at  the 
end  of  six  months  half  the  tubes  would  have  to  be  renewed  if  care  were  not 
taken  in  washing  out  and  cleaning,  and  it  used  to  be  said  that  the  water  of 
Bitter  Creek  would  cause  an  engine  to  leak  in  a  fortnight  when  the  Union 
Pacific  B,.  K.  first  reached  that  region. 

Among  the  forms  of  boilers  which  can  be  used  with  only  the  best  water, 
is  one  first  invented  by  Ogle  and  afterwards  modified  by  Prosser.  Two  sets 
of  tubes  were  used— a  long  and  short — and  four  tube  plates,  the  tube  which 
reached  from  the  first  to  the  fourth  tube  sheet  passed  through  the  short 


172 


STEAM  MAKING;  OB,  BOILER  PRACTICE. 


THE    BELLEVILLE    (FRANCE)    BOILER. 


MISCELLANEOUS  BOILERS,  ETC.  173 

tube  which  reached  from  the  second  to  the  third  tube  plate,  thus  passing 
tube  within  tube  a  chamber  was  formed  by  a  shell  from  the  first  to  the 
second  tube  sheet,  and  another  from  the  third  to  the  fourth.  The  water 
and  steam  occupied  the  space  in  these  two  chambers,  and  the  annular 
spaces  between  the  short  and  long  tubes,  provision  being  made  for  the 
descent  of  water  from  the  upper  to  the  lower  chamber  by  tubes  without 
internal  ones.  The  fire  was  underneath  in  a  furnace  chamber,  the  gas 
traversed  the  inside  of  the  long  tubes  vertically  to  a  connection  chamber, 
and  also  passed  outside  the  short  tubes  and  around  the  two  chambers  to 
the  smoke  connection  above.  When  this  arrangement  was  set  in  brick- 
work every  bit  of  surface  became  heating  surface,  end  by  carrying  a  low 
water  line  dry  steam  was  taken  from  the  upper  chamber  in  spite  of  the 
rapid  circulation  which  was  set  up  in  the  annular  spaces.  With  any  grease 
or  dirt  forming  scum,  this  boiler  inevitably  foamed,  and  no  way  existed 
for  examining  or  cleaning  the  inside  of  the  boiler  unless  made  of  excessive 
size;  the  outside  of  the  short  set  and  inside  of  the  long  set  of  tubes  could, 
however,  be  considered  as  fairly  accessible.  This  form  reappeared  years 
ago  in  New  York  where  it  was  modified  by  combination  with  a  fire  tube 
and  water  tube  addition  and  was  used  for  heating  a  building.  Nothing  but 
distilled  water  was  fed  into  the  boiler 

This  class  has  since  appeared  with  further  modification.  The  second 
and  third  tube  sheets  have .  been  united  by  an  iron  shell  and  connection 
made  between  the  chamber,  thus  formed,  and  the  steam  space  in  the  cham- 
ber above  it.  The  products  of  combustion  pass  only  up  through  the  long 
tubes,  while  the  middle  chamber  is  supposed,  while  acting  as  a  drum,  to 
also  act  as  a  submerged  drying  chamber.  The  complexity,  weight  for  a 
given  heating  surface,  and  difficulty  of  inspection  appear  to  be  all  in- 
creased by  this  arrangement. 

The  various  forms  of  pipe  boilers,  were  first  introduced  by  Jacob  Per- 
kins, very  many  years  ago.  We  may  note  two  types  at  this  day: 

The  continuous  line  of  pipe  in  which  the  water  is  forced  at  one  end 
and  from  which  steam  and  water  issue  at  the  other.  If  the  pipe  is  exposed 
near  the  outlet  to  a  great  heat  an  excess  of  water  must  be  pumped  through 
the  pipe  to  keep  it  from  burning;  if  on  the  other  hand  the  water  is  deliv- 
ered to  the  hot  end  of  the  pipe  no  excess  of  water  is  required.  In  the  lat- 
ter case  any  impurity  left  by  the  water  after  evaporation  will  be  deposited 
on  the  inside  of  the  pipe.  With  excess  of  feed  water  it  may  be  carried 
through  the  small  pipe  into  a  receiver  beyond.  There  may  be  one  line  of 
pipe  only,  as  in  Perkins',  Elder's  and  Herreshoffs,  or  more  than  one.  paral- 
lel line,  as  in  Benson's,  Lattas'  and  the  smaller  Belleville  forms. 

The  excess  of  feed  .water  carried  through  the  pipe  into  the  receiver 
may  be  blown  off  together  with  the  sediment  by  a  bottom  or  surface  blow- 
off  attached  to  the  receiver,  or  the  surplus  water  may  be  blown  into  the 
feed  supply,  thereby  warming  it;  in  either  case  being  supplied  to  the 
boiler  through  the  ordinary  feed  pump  along  with  the  feed  water,  or  it 
may  be  taken  from  the  receiver  itself,  and  circulated  through  the  pipe  re- 
turning to  the  receiver,  in  which  case  a  separate  pump  has  to  be  provided. 


174 


STEAM  MAKING;  OR,  BOILER  PRACTICE. 


MISCELLANEOUS  BOILERS,  ETC. 


175 


O  CL-.p 

°0o°60  ''o 


176  STEAM  MAKING;  OR,  BOILER  PRACTICE. 

The  form  of  the  line  of  pipe  has  received  many  changes.  Perkins'  has  a 
cylindrical  spiral;  with  Elder  a  conic  spiral;  with  Herreshoff  a  combination 
of  cylindrical,  conic  and  flat  spirals.  With  Benson  and  Belleville  a  series  of 
nearly  horizontal  pipes,  one  over  the  other,  connected  at  alternate  ends. 
The  form  of  receiver  used  was  a  vertical  cylinder  by  Elder,  Benson  and 
Herreshoff,  while  Belleville  uses  a  horizontal  cylinder  for  a  steam  drum 
connected  with  a  vertical  cylinder  used  as  a  mud- drum,  from  which  the 
blow-offs  are  led.  Latta  uses  for  his  receiver  a  vertical  annular  space  be- 
tween two  shells,  the  furnace  and  coils  of  pipe  being  inside  the  inner  one. 

Benson,  Latta,  and  Herreshoff  use  an  independent  circulating  pump. 
Belleville  in  the  small  boilers  blows  off  directly,  while  Elder  proposed  as  a 
circulator  a  small  screw  propeller  driven  from  outside. 

With  good  water  the  cost  of  blowing  away  the  surplus  feed  is  small  as 
this  water  has  not  been  evaporated,  but  in  some  cases  a  surface  condenser 
even  without  an  air  pump  is  used  in  order  to  secure  a  supply  of  good  water, 
for  example  at  sea  with  small  boats  and  engines.  The  cost  in  fuel  of  blow- 
ing off  into  this  reservoir  is,  of  course,  less..  The  quantity  of  excess  re- 
quired varies  with  the  intensity  of  the  combustion,  and  appears  not  to  ex- 
ceed one- half  more  than  the  feed,  the  waste  of  heat  is  then  not  likely  to 
exceed  12  per  centi  when  the  surplus  is  blown  away,  and  8  per  cent,  when 
the  feed  is  returned  to  the  balance  raising  it  to  a  high  temperature.  With  a 
circulating  pump  very  little  heat  is  lost.  With  water  containing  only  or- 
dinary impurities  these  classes  of  boilers  may  be  used  advantageously,  the 
excess  being  thrown  away;  but  with  sandy  and  muddy  water  it  is  always 
found  that  the  water  brought  in  the  feed  pipe  to  a  boiler  begins  to  de- 
posit solid  matter  outside  the  boiler,  and  to  fill  up  the  pipe  until  the  opening 
is  just  enough  to  supply  what  is  needed.  As  feed  pipes  are  usually  many 
times  the  size  required  for  this  purpose  (a  2-inch  pipe  often  closing  up  to 
less  than  £  of  an  inch)  it  is  readily  seen  that  if  the  feed  be  introduced,  as 
it  should  be  theoretically,  at  the  coolest  part  of  the  pipe,  this  may 
easily  happen  to  the  coil  pipe  itself,  and  then  that  some  accidentally  large 
portion  of  mud  accumulating  during  a  short  cessation  of  work,  would  either 
close,  or  so  nearly  close  the  already  contracted  passage,  and  the  por- 
tion of  pipe  exposed  to  the  greatest  heat  of  the  furnace  would  burn  before 
the  obstacle  would  wash  through.  A  boiler  containing  a  large  body  of 
water  is  not  so  soon  subjected  to  the  risk  of  burning. 

A  second  class  of  pipe  boilers  is  one  in  which  the  circulation  is  pro- 
vided for  only  by  gravity.  As  examples  of  this  we  have  the  Babcock  and 
Wilcox  (already  illustrated) ;  the  larger  Belleville,  and  the  Heine,  Boot  and 
Firmenich,  which  we  give.  The  latter  has  for  its  prototype  a  com- 
bination of  curved  pipes,  each  a  semi- circle,  uniting  two  straight  pipes  of 
greater  diameter  at  the  top  and  bottom  of  the  combination,  the  whole  be- 
ing that  two  horizontal  cylinders  are  joined  at  many  points  by  rings  in 
vertical  planes,  the  cylinders  being  at  the  top  and  bottom  of  the  vertical 
diameter  of  the  rings.  The  fire  was  made  in  the  inside  of  the  arrangement 
resting  on  the  rings  as  grate  bars,  and  the  feed  water  introduced  into  the 


MISCELLANEOUS  BOILERS,  ETC. 


177 


178  STEAM  MAKING;    OR,  BOILER  PRACTICE. 


BOILER    OF    THE    STEAMER    "ANTHRACITE.' 


iiiiiiiiiiiiiiiUlliiiiiiiiiiiHiiiiniiir 


MISCELLANEOUS  BOILERS,  ETC. 


179 


THE    FIRMENICH    BOILER. 


180  STEAM  MAKING;  OR,  BOILER  PRACTICE. 

lower  straight  pipe  branching  to  the  ring  pipes,  and  being  evaporated 
therein,  and  steam  taken  from  the  upper  straight  pipe. 

Of  course  with  poor  water  a  steam  drum  above  had  to  be  provided  so 
that  the  water  line  came  above  the  rings  and  a  circulation  either  through 
the  pipes  or  external  pipes  added  therefore. 

With  the  larger  Belleville  boilers  the  feed  is  introduced  into  a  vertical 
drum  and  then  crosses  the  steam  drum  in  a  kind  of  trough  to  the  vertical 
mud-drum,  whence  it  passes  down  to  the  distributing  drum.  With  the 
exception  of  the  passage  across  the  steam  drum  whereby  the  water  gets 
hot  enough  to  render  the  sulphates  and  carbonates  of  lime  insoluble,  and 
the  addition  of  a  circulating  pump,  the  arrangement  is  identical  with  that 
of  Benson.  Belleville  circulates  by  gravity  and  the  claim  is  that  from  four 
to  eight  times  the  water  evaporated  is  circulated.  Heine  also  uses  the  en- 
closed feed  heater  in  the  same  way,  only  the  outside  mud- drum  is  not  used, 
the  blow-offs  being  taken  from  the  enclosed  chamber. 

We  give  a  sketch  of  Ogle's  boiler  with  cuts  of  Heine's  as  built  at 
St.  Louis;  the  latest  type  of  Belleville's  and  Boot's,  and  a  sketch  of  one  of 
Herreshoff  s  smaller  boilers, — the  feed  being  into  the  outside  of  the  flat 
top  coil,  and  then  down  the  spirals  towards  the  fire  and  then  out  to  the 
separator.  In  many  cases  a  turn  or  two  of  pipe  in  the  furnaces  is  added 
after  the  steam  leaves  the  separator,  to  dry  or  superheat  the  steam.  A 
second  coil  of  spiral  pipe  was  added  on  the  outside  of  the  '-beehive  coil" 
in  order  to  increase  heating  surface,  and  other  coils  have  been  added  till 
one  of  the  latter  boilers  is  as  follows:  A  coil  of  small  pipe  fed  at  the  bot- 
tom passes  up  close  to  the  sheet-iron  shell,  three  flat  shells  come  next, 
followed  by  a  single  "beehive  coil."  The  Latta  boiler,  we  have  already  il- 
lustrated, and  we  add  a  cut  of  Firmenich's.  Belleville's  and  Boot's  boilers 
have  been  very  extensively  used  in  certain  localities.  Herreshoff  and  Latta 
have  had  great  success  with  special  applications — one  to  steam  yachts  and 
launches,  the  other  to  fire  engines. 

Closely  allied  is  the  boiler  now  used  by  Loftus  Perkins,  the  descendant 
of  Jacob  Perkins,  who  left  Newburyport,  Mass.,  for  England,  and  who  was 
the  originator  of  many  things  since  claimed  as  novelties,  some  unsuccessful, 
as  the  steam  gun  which  he  used  with  the  spiral  pipe  boiler,  some  since 
successful,  as  the  soft  iron  toothless  disc  now  used  for  cutting  steel  rails, 
cold,  which  he,  however,  only  tried  on  files  hardened. 

The  boiler  used  on  the  steamer  "Anthracite,"  consisted  of  140  horizon- 
tal pipes  in  10  layers,  14  in  a  layer  horizontally,  and  10  in  a  layer  vertically. 
These  are  united  vertically  by  short  nipples  of  small  pipe,  and  at  the 
top  each  of  the  14  pipes  of  the  top  layer  is  connected  at  the  middle  of  its 
length  to  a  transverse  pipe  of  larger  diameter,  acting  as  a  steam  drum. 
The  furnace  is  made  of  seven  rows  of  pipes  across  the  back  transversely  to 
upper  group,  seven  rows  on  each  side,  and  completed  rows  across  the 
front  two  rows  being  separated  in  the  centre,  and  two  shortened  rows 
leaving  an  opening  for  fire  door,  The  boiler  is  only  used  with  distilled 
water,  and  the  first  thought  we  have  is,  that  with  the  smallness  of  the  ris- 
ing pipes  and  the  lack  of  special  provision  for  circulation  or  return  of  water 


182 


STEAM  MAKING;  OR,  BOILER  PRACTICE. 


SHEPHERD'S    BOILER. 


THE    HERRESHOFF    BOILER. 


MISCELLANEOUS  BOILERS,  ETC.' 


183 


to  the  tubes  around  the  furnace,  we  should  expect  a  very  marked  "foam- 
ing" which  was  found  to  be  the  case  at  the  trial  made  by  a  Board  of 
United  States  Engineers,  United  States  Navy. 

We  also  give  a  sketch  of  an  element  of  section  of  Kelly's  boiler. 


ELEMENT  OF  A  SECTION  or  KELLY'S  BOILER. 


Hardly  lo  be  distinguished  from  the  water  tube>  or  tubulous  boilers, 
come  the  sectional  boilers,  such  as  Shepherd's  and  Cadiat's,  already  men- 
tioned, the  most  prominent  among  them  being  the  Harrison,  which  is 
made  of  cast  iron  globes  united  in  straight  lines  by  necks,  flanges  and 
bolts.  Each  line  of  globes  is  thus  a  straight  tube  with  alternate  enlarge- 
ments and  contractions,  and  the  boiler  is  subject  to  the  incidentals  of 
all  the  others  of  the  tubulous  class.  The  joints  are,  of  course,  much 
more  numerous  than  with  wrought-iron  tubes,  but  they  are  claimed  to  be 
easier  to  make  and  to  remain  in  better  order.  A  great  number  of  these 
boilers  have  been  in  satisfactory  use  in  the  eastern  part  of  the  United 
States,  and  elsewhere. 

We  may  then  sum  up  as  follows:  After  a  desirable,  and  counting  all 
things,  an  economical  evaporation  has  been  decided  upon,  and  the  grate 


184  STEAM  MAKING;  OR,  BOILER  PRACTICE. 

area  defined  from  the  fuel  consumption,  the  heating  surface  may  then  be 
computed  and  the  results  compared  with  the  available  experience.  That 
form  of  boiler  which  can  be  constructed  and  set  in  operation  for  the  least 
money,  without  lowering  the  quality  of  the  material  and  workmanship, 
and  without  interfering  with  the  quality  of  the  fuel  and  water, — in  brief 
its  durability, — is  the  one  to  be  recommended. 


APPURTENANCES  TO  A  BOILER. 


In  operating  boilers  a  multitude  of  fittings  and  tools  are  required. 
First,  as  to  the  furnace.  The  fireman  has  to  use  a  shovel  for  coal  and 
for  shavings  a  kind  of  push  hoe;  for  wood  his  hands  only  in  getting  the 
fuel  on  to  the  fire.  The  choice  of  a  shovel  depends  much  on  the  man, 
but  a  broad  flat  one  seems  favorable  to  spread  the  fuel  uniformly;  as  the 
coal  is  thrown  forward  the  shovel  is  struck  on  the  threshold  of  the  fire 
door  in  a  peculiar  manner  which  jerks  the  coal  upward  and  assists  in  the 
operation.  The  other  fire  tools  are  the  poker,  the  rake,  a  kind  of  hoe, 
a  slice  bar  for  running  up  through  the  grate,  and  a  flat  bar  for  lifting 
from  above  the  grate;  the  others  are  added  as  circumstances  require.  A 
shovel  for  removing  ashes  will  probably  be  required  in  addition  to  that 
used  for  firing. 

To  regulate  the  air  supply  a  damper  must  be  used,  placed  on  the 
door  in  the  flue  or  in  the  smoke  connection,  and  this  is  either  worked 
by  hand,  or  automatically.  The  fire  door  is  usually  supplied  by  a  register, 
which  is  sometimes  arranged  to  be  set  wide  open  by  the  act  of  closing  the 
door,  when  a  weight  falling  against  a  dash  pot  gradually  closes  it  again. 
This  was  one  of  the  earliest  attempts  to  prevent  smoke.  A  swinging  plate 
damper  in  the  stack  is  sometimes  connected  with  a  loaded  diaphragm,  or 
to  a  piston  in  a  cylinder  working  against  a  spring,  or  even  to  a  common 
safety  valve  lever.  When  the  pressure  of  steam  rises,  the  movement  of 
the  diaphragm  or  piston,  suitably  multiplied,  turns  the  damper  and 
reduces  the  draft.  As  the  pressure  falls  the  damper  is  opened  by  the 
reverse  action. 

In  supplying  feed  water  to  the  boiler  a  check- valve  is  placed  conven- 
iently close  to  the  shell,  or  point  of  attachment,  for  the  point  of  attach- 
ment of  the  feed  pipe  is  peculiarly  liable  to  be  strained  by  changes  of  tem- 
perature of  the  feed  water  as  well  as  the  fire,  consequently  an  extra  liability 
to  leakage  exists;  and  from  the  fact  that  this  connection  in  a  stationary 
boiler  is  usually  in  the  furnace,  a  great  deal  of  corrosion  takes  place,  and 
is  to  be  expected,  at  this  part.  The  joint  is  usually  made  by  screwing  the 
pipe  into  a  flange  secured  to  the  shell  by  bolts  or  rivets.  If  any  thing- 
happens  to  the  feed  water  apparatus,  such  as  the  leakage  of  a  valve,  or  any- 
thing which  requires  disconnecting  the  feed  pipes,  this  check  valve 
enables  it  to  be  done  without  delay.  It  also  acts  as  a  guard  and  relief  to 
the  discharge  valves  of  the  pump. 


MISCELLANEOUS  BOILERS,  ETC* 


185 


J31HI  U3J.VM  010? 


0.31  N I  KIV3JLS' 


186  STEAM  MAKING;  OR,  BOILER  PRACTICE. 

When  a  feed-water  heater  is  used,  it  may  be  placed  between  the  purnp 
and  boiler,  or  the  pump  may  be  placed  between  the  heater  and  boiler;  in 
the  former  case  any  ordinary  form  of  feed  pump  may  be  employed,  but 
the  feed  water  must  be  separate  from  the  exhaust  steam  used  for  heating, 
for  the  feed  water  must  be  at  the  boiler  pressure,  while  the  exhaust  steam 
is  of  course  near  the  atmospheric  pressure.  By  using  a  jet  of  fine  steam  to 
raise  the  upper  portion  only  of  the  water  which  is  in  the  heater,  the  lime 
salts  may  be  rendered  insoluble,  and  can  be  caught  in  a  quiet  pan,  or  blown 
off  at  the  surface.  This  is  Strong's  heater.  No  economy  of  fuel  is  obtained 
by  the  use  of  live  steam,  its  effect  is  the  purification  of  the  water.  On  the 
other  hand,  if  the  feed  water  pass  first  into  the  heater,  any  kind  of  a  heater 
may  be  employed;  but  the  pump  valves  must  be  prepared  to  take  hot 
water,  and  it  is  desirable  to  have  the  feed  water  supplied  to  the  force 
pumps  from  a  higher  level,  so  that  no  attempt  at  suction  may  be  required, 
for  the  water  gives  off  steam  in  large  volumes  at  a  very  slight  reduction 
below  the  pressure  of  the  atmosphere,  and,  filling  the  pump  chambers, 
interferes  with  its  satisfactory  working. 

We  give  a  few  forms  of  heaters  used,  but  do  not  think  it  advisable  to 
enter  more  fully  into  the  subject.  In  a  great  portion  of  the  western  prac- 
tice a  closed  cylinder  set  horizontally  is  used,  which  is  filled  with  the  feed 
water  to  about  half;  the  exhaust  steam  from  the  engines  is  then  passed  over 
the  surface  of  the  water,  which  is  held  by  blades  from  being  taken  along  with 
the  steam,  for  the  exhaust  steam  often  leaves  the  cylinder  at  a  pressure  of 
75  pounds  to  the  inch.  With  the  heater  just  described  two  sets  of  pumps 
are  employed,  one  to  lift  from  the  ground,  or  well,  to  the  heater,  a  work 
which  may  be  omitted  if  the  supply  be  high  enough,  and  the  other  a  force 
pump,  filling  by  gravity  from  the  heater,  usually  placed  above  the  pumps, 
and  forcing  into  the  boiler.  The  favorite  western  arrangement  is  a  beam, 
crank  and  fly-wheel  engine  working  two  lifting  pumps  on  one  side,  and 
two  force  pumps  on  the  other  side  of  the  beam,  the  feed  being  carried 
through  the  hollow  columns  which  support  the  heater.  The  whole 
arrangement  goes  by  the  name  of  "doctor."  Although  the  machine  can 
hardly  be  surpassed  for  general  ugliness  of  appearance,  yet  it  is  eminently 
adapted  to  the  work  to  be  done,  and  all  attempts  to  drive  it  from  the  boats 
on  the  river,  and  its  vicinity,  have  failed,  for  it  represents  a  long  experi- 
ence with  a  peculiar  set  of  conditions. 

The  feed  pumps  used  are  either  attached  to  the  main  engine,  or 
driven  by  an  independent  steam  engine,  and  in  no  one  point  of  practice 
is  there  more  universal  disagreement  on  the  two  sides  of  the  Atlantic. 
In  England  and  Europe  the  attachment  of  the  pump  to  the  engine  is  a 
matter  of  course,  and  even  the  smallest  engines  are  provided  with  them: 
it  is  only  in  large  engines,  driving  mills,  or  where  a  number  of  engines 
are  employed,  or  the  water  is  used  for  something  else,  that  an  independent 
pumping  engine  is  used.  The  argument,  which  can  not  be  contradicted,  is, 
that  it  costs  less  steam,  hence  fuel,  to  do  the  work  of  pumping,  is  but  a  small 
addition  to  the  work  of  the  engine,  £%50  per  cent,  if  the  water  used  be  30 
pounds  per  horse  power  per  hour,  and  the  steam  pressure  100  pounds  above 


MISCELLANEOUS  BOILERS,  ETC.* 


187 


the  atmosphere,  and  varying  directly  with  the  steam  pressure  and  the 
economy  of  the  engine — than  by  a  small,  non- expanding,  slow  work- 
ing engine.  In  the  United  States  this  was  also  the  practice,  but  at  present 
the  use  of  the  independent  engine  is  universal,  and  it  is  beginning  to  be 
introduced  into  England  from  this  country.  The  chief  merit  is  in  its  being 
able  to  run  when  the  engine  is  shut  down,  and  to  vary  the  quantity  of  feed 


while  the  uniformity 
is  not  interfered  with, 
the  security  of  the 
be  suddenly  stopped, 
will  not  stop  with  a 
course  the  supply 
but  from  being  almost 
looked  after  it  be- 
ary  matter.  As  in  a 
power  can  be  fur- 
at  a  cost  of  from  20  to 
per  hour,  while  with 
quently  met  with,  this 
60  to  100,  or  say,  three 
independent  engine, 
gives:  With  a  boiler 
pounds  of  water  for  1 
see  that  it  might  take 
the  worst  case  we 
against  3  for  the  best 
14  pounds  per  hour, 
for  each  horse  power 
pressure  is  100  pounds 
feet,  =  4,600  foot- 
power  per  hour,  and 
cates  100  horse  power, 
100,  or  460,000  foot- 
required  to  pump  the 
Now,  a  horse  power  is 
erted  for  a  second, 
1,980,000  for  an  hour, 
fourth  a  horse  power, 
about  one -fourth  of 
pounds,  of  coal  a  day, 
greatest  difference  in 
with,  or  say  40  as  a 


SECTION  OF  CRANK,  AND  FLY 
WHEEL  FEED  PUMP. 


of  speed  of  the  engine 
The  former  adds  to 
boiler  if  the  engine 
for  the  water  supply 
big  fire,  when  of 
should  be  moderated, 
the  first  thing  to  be 
comes  a  very  second- 
good  engine  a  horse 
nished  from  the  boiler 
30  pounds  of  water 
the  small  one,  as  fre- 
cost  amounts  to  from 
times  as  much  for  the 
Let  us  see  what  this 
evaporation  of  6 
pound  of  steam,  we 
17  pounds  of  fuel  for 
have  supposed 
engine,  a  difference  of 
or  140  pounds  per  day 
required.  If  the  steam 
we  have  20  Ibs.  X  230 
pounds  per  horse 
if  the  engine  indi- 
we  shall  have  460  x 
pounds,  as  the  energy 
feed  for  an  hour. 
550  foot  pounds  ex- 
or  33,000  a  minute,  or 
This  is  about  one- 
which  would  require 
the  140  pounds,  35 
assumed  to  be  the 
cost  likely  to  be  met 
limit,  an  expense 


ranging  from  3  to  25  cents  a  day,  according  to  the  price  of  fuel. 

If,  on  the  other  hand,  the  main  engine  requires  40  pounds  of  water 
per  horse  power  per  hour,  the  quantity  required  for  our  100  horse  engine, 
with  100  pounds  of  steam,  will  be  twice  as  great,  or  about  one-half  a 
horse  power;  and  if  now  we  have  a  feed  pump  of  proper  proportions, 


188 


STEAM  MAKING;  OR,  BOILER  PRACTICE. 


we  have,  for  half  a  horse-power,  30  Ibs.  of  water,  and  for  a  boiler  evapora- 
tion of  9  in  place  of  6,  3.3  pounds  of  coal,  used  by  the  independent  engine. 
An  engine  using  20  Ibs.  of  water  gives  the  same  result,  viz.,  11  Ibs.  per 
day  difference  iu  place  of  40  Ibs.  The  convenience  and  security  of  a  sep- 
arate pump  would  seem  to  far  outweigh  this  slight  economy. 

Of  the  multitude  of  steam  pumps  made  we  find  two  classes,  the  direct 
acting  and  the  crank  and  fly  wheel.    The  latter  are  more  economical  in 


using  steam,  as  the  steam 
but  it  may  be  doubted  if 
caused  by  the  greater 
do  not  overbalance  this, 
economy  claimed  can  not 
just  investigated,  where 
to  the  main  engine. 

With  the  choice  of  a 
shall  have  little  to  do. 
pairs,  or  collectively,  the 
is  the  item  to  be  gov 
necessarily  in  different 
times.  This  is  not  always 
we  have  seen  that  the 
must  be  of  comparative 
shall  dismiss  the  subject 
make  a  choice  among  the 
in  the  market. 

We  illustrate  only 
made  in  this  country,  as 
adapted  to  any  work. 

The  use  of  a  jet  or 


may  be  used  expansively, 
the  additional  couplings 
number  of  connections 
because,  of  course,  the 
reach  that  which  we  have 
the  pump  was  attached 

boiler  feed  pump  we 
The  cost,  and  cost  of  re- 
annual  cost  of  the  pump 
erned  by,  and  this  varies 
localities  and  at  different 
an  easy  matter  to  do,  but 
difference  among  them 
unimportance,  and  we 
without  attempting  to 
many  excellent  machines 

one  form  of  pump,  not 
simple  and  seeming  well 

stream  of  fluid  across  the 


line  of  motion  of  another  ELEVATION  or  CRANK  AND   stream  of  fluid  to  com- 


municate motion  from  FLY-WHEEL  FEED  PUMP,  the  first  stream  to  the 
second  stream  has  long  been  known.  A  stream 

of  water  acting  at  high  pressure,  400  Ibs.,  in  a  2-inch  pipe  upon  a  second 
stream,  had  the  power  to  lift  a  column  of  water  120  feet  in  a  6-inch  pipe, 
bringing  with  it  an  immense  quantity  of  sand  and  gravel.  We  have  here 
a  convincing  example  of  one  stream  contributing  enough  of  its  energy  to 
move  the  other  two,  one  of  water  and  one  of  sand,  while  the  resulting 
velocity  is  that  due  to  the  energy  of  the  first  stream  acting  upon  the 
whole  mass.  A  second  example,  which  we  will  discuss  later,  is  a  jet  of 
steam  to  set  a  current  of  air  in  motion. 

The  use  of  a  jet  of  steam  for  moving  a  stream  of  water  originated  the 
steam  syphon,  and  various  other  forms  of  the  steam  jet  pump,  a  useful 
adjunct  to  locomotives  in  a  new  country. 

The  energy  of  motion  of  a  body  is  well  known  to  be  the  product  of 
its  mass  by  the  half  square  of  its  velocity,  hence  it  is  possible  to  com- 
municate to  a  body  of  little  weight  a  large  amount  of  energy  by  moving  it 
fast  enough,  and  in  fact  the  energy  of  motion  would  only  be  limited  by 


MISCELLANEOUS  BOILERS,  ETC.1 


189 


VATEft 


INJECTORS. 


the  speed  which  can  be  given  the  body.  In  this  way  a  small  weight  of 
steam  flowing  from  an  orifice  into  a  properly  shaped  jet  of  water  is  con- 
densed while  the  velocity  of  the  steam  is  greater  than  if  flowing  into  air; 
the  energy  thus  communicated  is  made  sufficiently  great  by  increasing 
the  weight  of  steam,  which  can  be  done  by  increasing  the  area  of  the 
steam  way,  until  we  find  such  jet  pumps  adapted  to  many  purposes. 
There  are,  however,  two  which  are  of  interest  to  us  in  this  connection,  or 
rather  only  one  with  a  modification.  The  well  known  injector  invented 
by  M.  Henri  Giffard,  and  its  large  family  of  lifting  and  non-lifting  varieties, 
all  differing  in  details  as  to  form  of  nozzles,  area  of  passages,  distances 
between  nozzles,  and  that  class  of  instruments  in  which,  after  a  certain 
energy  and  velocity  have  been  reached,  the  operation  is  repeated.  These 
might  be  called  "consecutive"  instruments.  Our  illustration,  Fig.  1,  shows 
one  of  the  simplest  non-adjustable  kinds.  Within  a  few  years  this  princi- 


190 


STEAM  MAKING;  OR,  BOILER  PRACTICE. 


pie  of  increase  of  energy  by  increase  of  mass  or  velocity  has  been  applied 
by  increasing  the  mass  of  steam  used  until  we  find  that  not  only  can  a 
few  pounds  weight  of  steam  put  into  a  boiler  a  good  many  more  pounds  of 
water  at  a  much  higher  temperature  than  it  had,  but  that  in  a  non-con- 
densing engine  it  is  possible,  by  using  the  exhaust  steam  in  part,  to  put 
into  the  boiler  at  a  much  higher  pressure  and  temperature,  a  weight  of 
water  which  is  still  greater  than  that  of  the  steam  moving  it. 


FORCING 


FORCING 


STATIONARY. 


LOCOMOTIVE. 


INJECTORS. 


When  the  injector  first  made  its  appearance,  it  was,  by  many,  consid- 
ered as  almost  a  paradox,  especially  by  those  who  looked  at  the  question 
as  one  of  hydrostatics  only.  That  steam  from  a  boiler  could  put  water 
back  into  it  at  the  same  pressure,  and  overcome  the  friction  of  the  pass- 
ages without  the  aid  that  a  steam  pump  had  of  a  difference  of  piston  areas, 
was  to  them  a  puzzle.  The  use  of  exhaust  steam  at  atmospheric  pressure 
for  the  purpose  of  putting  water  into  a  boiler  at  a  pressure  of  150  pounds 
per  square  inch  would  be  to  such  minds  utterly  incomprehensible.  We 
think  there  are  two  classes  of  instruments  made  for  the  difference  in  steam 
pressures  below  and  above  60  pounds,  differing  in  area  and  disposition  of 
the  passages. 

As  this  modification  is  one  of  the  latest,  so  it  is  not  one  of  the  most 
important,  for  we  have  seen  that  the  cost  of  the  feed  water  put  into  the 
boilers  was  from  one-fourth  to  one-third  of  1  per  cent.  Now,  a  horse 
power  with  the  best  engine  and  boiler,  non-condensing  engine,  runs 
from  2£  to  3£  Ibs.  of  coal  per  hour,  a  value  by  the  way  corresponding  to  an 


MISCELLANEOUS  BOILEliS,  ETC.9  191 

average  between  the  £  and  £  of  1  per  cent,  given  above,  the  former  being 
taken  for  a  condensing  engine  using  20  flbs.  of  water,  the  latter,  25  Tbs., 
giving  with  10  for  evaporation,  2|  Ibs.  of  coal  per  hour  per  indicated 
horse  power.  If,  now,  the  engine  runs  500  indicated  horse  power  24  hours 

24  x  500  x  7  x  5 
in  the  day,  we  have          24.00  x  2 '  quantities  are  then, 

24  hours  per  day. 
500  horse  power. 
7 
2400  tlie  avera&e  between  £  and  £  per  cent. 

2     the  2£  Ibs.  of  coal  required  for  one  horse  power. 

This  costs  from  5  to  25  cents  per  day,  or  from  $15  to  $75  per  year,  the 
feed  water  being  delivered  at  a  temperature  of  about  150°  F.,  and  the 
cost  of  a  heater  being  saved  in  addition.  We  see,  therefore,  that  the  feed 
water  cnn  easily  be  put  into  the  boiler,  and,  as  we  have  seen  elsewhere, 
all  that  can  be  saved  from  the  expense  is  so  much  net  gain,  while  it  is 
evident  from  our  investigation,  that  more  can  be  saved  by  the  use  of 
a  first-class  heater,  leaving  the  water,  say  at  200°  F.,  and  then  taking  out 
what  is  used  by  the  pump,  tban  by  an  exhaust  injector,  as  this  modifica- 
tion is  known. 

The  use  of  an  injector  has  this  to  recommend  it,  that  the  feed  water 
can  not  be  introduced  into  the  boiler  cold  or  nearly  so,  but  must  be 
warmed  by  contact  with  the  steam,  and  the  value  of  this  has  been  already 
shown.  In  small  boilers  where  no  heater  is  used  an  exhaust  injector  is 
better  than  a  pump,  and  so  is  an  ordinary  injector;  but  the  former  includes 
in  itself  an  exhaust  heater,  saving  a  portion  of  heat  from  the  exhaust, 
besides  taking  the  power  as  heat  also,  while  with  the  common  injector  the 
heat  for  power  and  raising  temperature  are  both  derived  from  the  live 
steam  in  the  boiler.  The  latter  portion  of  heat  is,  of  course,  directly 
returned  to  the  boiler  without  loss,  but  that  for  power  is  necessarily  ex- 
pended. As  to  the  amount  of  power  used  by  pump  and  injector  compared 
with  each  other,  it  would  seem  that  the  pump  is  most  efficient.  There 
have  been  many  comparative  trials  of  pump  and  injector,  but  the  results 
have  usually  been  unsatisfactory  from  contained  discrepancies.  We  may, 
however,  sum  up  our  impressions  as  follows: 

For  engines  with  condensers,  either  a  pump  or  common  injector  may 
be  used. 

For  engines  with  jet  condensers,  an  injector  is  to  be  preferred  to  a 
pump,  as  the  temperature  of  the  feed  is  necessarily  much  higher  than  the 
hot  well.  This  preference  is  not  because  of  economy  of  fuel  but  dura- 
bility of  the  boiler. 

For  non-condensing  engines,  in  order  of  choice,  a  pump  and  first- 
class  heater,  an  exhaust  injector,  a  common  injector. 

The  exhaust  injectors  have  not  vet  been  used  enough  to  develop  their 
full  capabilities,  but  there  is  no  reason  to  doubt  that  in  a  few  years  the 
same  confidence  should  be  felt  in  them  as  in  the  older  forms. 


192  STEAM  MAKING;  OR,  BOILER  PRACTICE. 

We  illustrate  only  a  simple  form  of  injectors,  in  sections;  these  are 
not  made  in  this  country. 

The  application  of  a  steam  jet  to  induce  a  current  of  air  for  draft  is 
nearly  as  old  as  the  locomotive  with  which  it  originated  and  to  which  its 
use  now  is  almost  restricted,  and  to  boilers  of  the  same  class  where  a  sud- 
den call  for  steam  can  be  rapidly  met.  In  the  most  simple  form  a  pipe  is 
led  from  the  boiler  to  the  stack,  if  of  iron,  if  not,  to  some  of  the  flues  or 
tubes,  which  is  terminated  by  a  reducer  with  short  nipple;  a  1"  pipe  with 
a  §"  or  £"  nipple,  sufficing  to  raise  the  gauge  from  20  to  90  Tbs.  in  7  minutes 
for  a  100  horse  power  engine. 

The  chimney  used  in  this  case  was  18  inches  diameter  and  25  feet  high. 

For  plain  jets  and  nozzles  of  this  class  in  open  cylinders,  Mr.  J.  A. 
Langridge,  Member  Institution  of  Civil  Engineers,  concludes  essentially: 

1.  The  action  is  due  the  friction  of  one  fluid  on  the  other,  and  that  by 
dividing  the  jets  the  surface  of  contact  of  the  fluids  is  much  increased  for 
the  same  masses  of  fluid;   or  the  same  draft  may  be  produced  with  less 
steam. 

2.  The  effect  of  the  draft  is  increased  by  lengthening  the  chimney, 
but  the  effect  is  smaller  from  four  diameters  to  eight  diameters  than  less 
than  four  diameters.    Above  eight  there  is  a  falling  off. 

3.  He  states  that  the  draft  measured  in  inches  of  water,  inches  of 
diameter  and  pounds  per  square  inch  above  the  atmosphere,  may  be  com- 
puted as  follows: 

Draft  equals  37  times  the  fifth  power  of  the  third  root  of  the  diameter 
of  the  blast  pipe,  times  the  fourth  power  of  the  fifth  root  of  the  pressure, 
divided  by  the  square  of  the  diameter  of  the  chimney. 

Very  much  better  results  are  obtained  by  giving  proper  form  to  the 
nozzle  and  guiding  surfaces  around  the  jets. 

Blow-off  valves  are  used  at  the  bottom  and  surface;  the  former  are 
used  intermittently,  and  as  their  use  includes  running  out  all  the  water  in 
the  boiler  when  it  is  desired  to  remove  it,  they  are  quite  large,  and  should, 
as  before  noted,  have  sliding  gate  with  room  for  mud.  The  attachment  to 
the  shell  of  such  a  large  pipe  should  be  by  flange.  The  upper  blow-off 
usually  takes  its  water  from  such  a  place  in  the  boiler  that  a  well  defined 
down  current  follows  a  horizontal  one.  At  this  angle  the  water  is  com- 
paratively quiet.  Another  method  is  to  provide  an  inside  pan  where  the 
water  is  shielded  from  upward  streams  and  bubble,  where  the  scum  on  the 
surface  may  have  a  chance  to  form.  Sometimes  a  drum  outside  the  boiler 
is  connected  at  two  points  with  this  pan  and  the  circulation  set  up  by 
differences  of  temperature  brings  the  water  out  with  its  impurities; 
the  latter  have  time  to  settle,  or  if  not  cooled  sufficiently,  remain  at  the 
surface  and  are  there  removed.  The  action  of  a  surface  blow-off  may 
be  intermittent  or  constant.  In  the  latter  case  a  loss  of  heat  occurs  which 
we  have  fully  discussed  in  this  chapter. 

Gauge  cocks  are  put  in  at  different  levels  near  the  water  line.  The 
lowest  is  usually  put  in  so  that  a  full  gauge  of  water  lies  over  the  danger 
point,  or  highest  metal  exposed  to  the  direct  action  of  the  hot  gas  on  the 


COMBINATION   GAUGE. 


v^™^ 

UNir 


TYPE   OF   SAFETY  VALVE  FOR 
MARINE  BOILERS. 


ORDINARY 
SAFETY 
VALVES. 


STEAM    GAUGES. 


FORGED    WROUGHT   IKON   MAN   HOLE  AND    COYER. 


CORRUGATED    FLUE. 


MISCELLANEOUS  BOILEES,  ETC.  195 

second  return  thereof.  The  cocks  are  in  number  from  two  up,  three,  or 
four  in  all,  being  the  common  number.  The  upper  one  is  placed  at  as  high 
a  level  as  it  is  thought  can  be  used  without  foaming.  In  addition,  one  or 
two  glass  tubes  are  sometimes  used.  The  brass  fittings  in  which  the  latter 
are  inserted  should  be  provided  with  four  valves,  one  between  the  glass 
and  boiler  at  each  end  of  the  tube,  and  one  at  each  end  in  the  line  of  the 
tube,  so  it  can  be  cleaned  by  washing  from  either  end  and  a  rod  can  be  run 
through  it.  The  tube  is  packed  in  place  by  gum  washers  and  double  nuts. 
Specially  soft  glass  has  to  be  used,  and  great  care  taken  not  to  scratch  the 
glass,  or  a  break  is  sure  to  happen.  By  shutting  off  the  glass  from  the 
boiler  it  can  easily  be  replaced. 

We  illustrate  a  combined  gauge  glass  and  gauge  cocks. 

A  float  inside  the  boiler  attached  to  two  arms  on  a  spindle  passing 
through  the  head  of  the  boiler  in  a  properly  packed  box,  varies  with  the 
water  and  shows  its  position  by  a  needle  attached  to  the  spindle.  The 
constant  fluctuations  of  these  instruments  show  them  to  be  in  working 
order,  but  the  gauge  cock  should  be  used  every  hour. 

Safety  valves  are  loaded  by  dead  weight,  weight  and  lever,  direct 
springs,  and  spring  and  lever.  The  valves  are  usually  plain  cones,  but  of 
late  years,  the  portion  beyond  the  cone  has  been  modified  in  a  manner 
easily  seen  from  the  illustrations. 

The  most  important  adjunct  of  a  boiler  is  the  pressure  gauge. 

Pressure  gauges  are  made  either  with  diaphragm,  as  a  spring  against 
which  the  steam  presses,  or  by  a  flattened  curved  tube  which  tends  to 
become  circular  in  section  with  increase  of  pressure. 

The  last  adjunct  of  a  boiler  is  the  manhole  and  its  cover  and  the  hand 
holes.  The  common  form  is  too  well  known  for  description,  but  we  give 
an  illustration  of  a  forged  wrought  iron  fitting,  with  cover  bolted  on  a 
ground  joint.  In  this  country  such  a  forging  would  be  found  difficult, 
but  we  have  a  few  made  of  gun  metal,  or  "gun"  cast  iron. 

In  conclusion  we  give,  in  addition  to  the  many  cases  among  our  boiler 
illustrations,  a  drawing  of  one  of  the  corrugated  flues,  or  furnace  tubes. 


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